JP7352033B2 - mist inhaler - Google Patents

Description

Cross-References to Related Applications This application claims the benefit of each priority and is incorporated by reference in its entirety. U.S. Patent Application No. 17/122025, filed December 15, 2020, and U.S. Patent Application No. 17/220189, filed April 1, 2021.

The present invention relates to a mist inhaler. The present invention relates more particularly to ultrasonic mist inhalers for atomizing liquids containing therapeutic agents for inhalation by a user.

Mist inhalers are used to generate a mist or vapor for inhalation by a user. The mist can contain therapeutic agents, drugs, or pharmaceuticals that are inhaled by the user and absorbed into the user's bloodstream.

Therapeutic aerosol delivery has become a mainstay of treatment for asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis. Therapeutic aerosols have also been applied in the treatment of influenza and osteoporosis, and in the delivery of vaccines.

Pulmonary delivery of therapeutic agents for the treatment of non-respiratory systemic diseases is attractive due to high pulmonary vascularity, thin blood-alveolar barrier, large surface area, avoidance of gastric enzymes, and hepatic first-pass metabolism. It is. Also attractive is improved patient comfort and compliance. The pulmonary system can be exploited for the delivery of antibodies, proteins, painkillers, and nucleic acids. Treatment of central nervous system diseases such as tobacco addiction could be significantly improved by efficiently delivering nicotine through the lungs and into the systemic circulation.

The effectiveness of therapeutic aerosols is related to the amount of drug deposited beyond the oropharyngeal region. The area where deposition occurs is a function of the size of the inhaled particles.

Devices currently used for administering inhaled drugs are classified into three categories: nebulizers, metered dose inhalers, and dry powder inhalers. Nebulizers are generally divided into two types: jet type and ultrasonic type, but in conventional devices, both types have weaknesses and problems.

Jet nebulizers are based on the Bernoulli principle and produce relatively large droplets, which generally deposit in the oropharynx and are not particularly effective. Ultrasonic nebulizers use piezoelectric crystals that vibrate at a frequency of 1 MHz to 1.7 MHz, transferring vibrational energy to a liquid and converting it into an aerosol. It is recognized that ultrasonic nebulizers are not effective when viscous suspensions or solutions are used and tend to heat the drug and therefore destroy the molecules, removing the benefits of inhalation. .

Accordingly, there is a need in the art for an improved mist inhaler that seeks to address at least some of the problems described herein.

The present invention provides a mist inhaler according to claim 1. The invention also provides preferred embodiments as set out in the dependent claims.

Various examples of the present disclosure described below have multiple advantages and benefits compared to conventional mist inhalers. These advantages and benefits are described in the description below.

Because the example mist inhaler of the present disclosure is capable of more efficient operation than conventional mist inhalers, the example mist inhaler of the present disclosure provides environmental benefits due to reduced power requirements. have.

According to one aspect, a mist inhaler for producing a mist for inhalation by a user is provided, the device comprising:
A mist generator that includes:
A mist generator housing that is elongate and includes an air inlet port and a mist outlet port; A liquid chamber within the mist generator housing for containing a liquid to be atomized; a sonication chamber; a capillary element extending between a liquid chamber and a sonication chamber, wherein a first portion of the capillary element is within the liquid chamber and a second portion of the capillary element is within the sonication chamber; an ultrasonic transducer having a generally planar atomizing surface disposed within an ultrasonic processing chamber such that the plane of the atomizing surface is substantially parallel to the longitudinal length of the mist generator housing; The ultrasonic transducer is mounted within the mist generator housing such that the ultrasonic transducer is parallel. A portion of the second portion of the capillary element overlaps a portion of the atomization surface, and the ultrasonic transducer causes the atomization surface to vibrate to cause the atomization to be carried by the second portion of the capillary element. The ultrasonic processing apparatus according to claim 1, characterized in that the ultrasonic processing apparatus is configured to atomize a liquid to generate a mist of the atomized liquid and air in the ultrasonic processing chamber. port, an airflow arrangement providing an air flow path between the sonication chamber and the pre-air outlet port, the airflow arrangement being configured to allow a user to draw air from the mist exit port through the inlet port and through the sonication chamber. a mist inhalation device that exits through a mist exit port and in which the mist generated within the sonication chamber is carried by air through the mist exit port for inhalation by a user, further comprising: :
Driver device containing:
Battery AC driver that converts the voltage from the battery into an AC drive signal of a predetermined frequency to drive the ultrasonic transducer Active power used by the ultrasonic transducer when the ultrasonic transducer is driven by the AC drive signal an active power monitoring arrangement for monitoring an ultrasonic transducer, the active power monitoring arrangement providing a monitoring signal indicative of the active power used by the ultrasonic transducer; and controlling an AC driver and receiving a monitoring signal drive from the active power monitoring arrangement. A memory that stores instructions that, when executed by a processor, cause the processor to:
A. Controlling the AC driver to output an AC drive signal to the ultrasonic transducer at a predetermined sweep frequency B. C. Calculate the active power being used by the ultrasound transducer based on the monitoring signal. Control the AC driver to modulate the AC drive signal to maximize the active power used by the ultrasound transducer D. E. Storing in memory a record of the maximum active power used by the ultrasound transducer and the sweep frequency of the AC drive signal. Repeat steps AD a predetermined number of times, with each iteration increasing or decreasing the sweep frequency such that after a predetermined number of iterations, the sweep frequency increases or decreases from the sweep start frequency to the sweep end frequency.F. Determine from the records stored in memory the optimal frequency of the AC drive signal, which is the sweep frequency of the AC drive signal at which maximum active power is used by the ultrasound transducer.
G. The AC driver is controlled to output an AC drive signal to the ultrasonic transducer at an optimal frequency to drive the ultrasonic transducer and atomize the liquid.

In some examples, the driver device is releasably attached to the mist generator such that the driver device is separable from the mist generator.

According to another aspect, a mist generator is provided that incorporates:
A mist generator housing that is elongate and includes an air inlet port and a mist outlet port; A liquid chamber within the mist generator housing for containing a liquid to be atomized; a sonication chamber; a capillary element extending between a liquid chamber and a sonication chamber, wherein a first portion of the capillary element is within the liquid chamber and a second portion of the capillary element is within the sonication chamber; an ultrasonic transducer having a generally planar atomizing surface disposed within an ultrasonic processing chamber such that the plane of the atomizing surface is substantially parallel to the longitudinal length of the mist generator housing; The ultrasonic transducer is mounted within the mist generator housing such that the ultrasonic transducer is parallel. A portion of the second portion of the capillary element overlaps a portion of the atomization surface, and the ultrasonic transducer causes the atomization surface to vibrate to cause the atomization to be carried by the second portion of the capillary element. 2. The ultrasonic processing apparatus according to claim 1, wherein the ultrasonic processing apparatus is configured to atomize a liquid to generate a mist consisting of the atomized liquid and air in the ultrasonic processing chamber. providing an air flow path between the air inlet port, the sonication chamber, and the air outlet port such that a user suctioning at the port passes through the inlet port, through the sonication chamber, and out through the mist outlet port; In some instances, the mist generator includes an airflow arrangement and a mist inhaler in which the mist generated in the sonication chamber is carried out by air through a mist exit port for inhalation by the user. The following is provided: a transducer holder held within the mist generator housing, the transducer element holding the ultrasonic transducer and a second capillary element superimposed on a portion of the atomizing surface. a transducer holder for holding a portion of the first portion of the capillary element; and a partition for providing a barrier between the liquid chamber and the sonication chamber, the partition defining a capillary opening through which a portion of the first portion of the capillary element extends. The device further includes a partition portion.

In some examples, the transducer holder is liquid silicone rubber.

In some examples, the liquid silicone rubber has a hardness of Shore A60.

In some examples, the capillary opening is an elongated slot having a width of 0.2 mm to 0.4 mm.

In some examples, the capillary element is generally planar with a first portion having a generally rectangular shape and a second portion having a partially circular shape.

In some examples, the capillary element has a thickness of substantially 0.28 mm.

In some examples, the capillary element is comprised of a first portion and a second portion that are stacked on top of each other such that the capillary element has two layers.

In some examples, the capillary element is at least 75% bamboo fiber.

The capillary element is 100% bamboo fiber.

In some examples, the airflow arrangement is such that the airflow is substantially perpendicular to the atomization surface of the ultrasound transducer as it passes into the sonication chamber. configured to change the direction of air flow along the path.

In some examples, the airflow direction change is substantially 90°.

In some examples, the airflow arrangement provides an airflow path having an average cross-sectional area of substantially 11.5 mm ² .

In some examples, the mist generating device includes: at least one absorbent element located adjacent to the mist exit port to absorb liquid at the mist exit port.

In some examples, each absorbent element is bamboo fiber.

In some examples, the mist generator housing is at least partially a heterophasic copolymer.

In some examples, the heterophasic copolymer is polypropylene.

In some examples, the ultrasound transducer is circular and has a diameter of substantially 16 mm.

In some examples, the liquid chamber contains a liquid having a kinematic viscosity between 1.05 Pa-s and 1.412 Pa-s and a liquid density between 1.1 g/ml and 1.3 g/ml. including.

In some examples, the liquid chamber includes a liquid that includes nicotine levulinate salt in a 1:1 molar ratio.

In some examples, the mist generator further comprises an identification arrangement disposed on the mist generator housing, the identification arrangement in communication with an integrated circuit having a memory that stores a unique identifier for the mist generator device. with electrical connections that provide an electronic interface for

In some examples, the memory of the integrated circuit stores a record of the state of the mist generator that is indicative of at least one of historical use of the mist generator or a volume of liquid within the liquid chamber.

According to one aspect, a driver device for a mist inhaler is provided, the device comprising:
Battery AC driver that converts the voltage from the battery into an AC drive signal of a predetermined frequency to drive the ultrasonic transducer Converts the effective power used by the ultrasonic transducer when the ultrasonic transducer is driven by the AC drive signal. an active power monitoring arrangement for monitoring and providing a monitoring signal indicative of active power used by the ultrasound transducer; and for controlling an AC driver and receiving a monitoring signal drive from the active power monitoring arrangement. A memory that stores instructions that, when executed by a processor, cause the processor to:
A. Controlling the AC driver to output an AC drive signal to the ultrasonic transducer at a predetermined sweep frequency B. C. Calculate the active power being used by the ultrasound transducer based on the monitoring signal. Control the AC driver to modulate the AC drive signal to maximize the active power used by the ultrasound transducer D. E. Storing in memory a record of the maximum active power used by the ultrasound transducer and the sweep frequency of the AC drive signal. Repeat steps AD a predetermined number of times, with each iteration increasing or decreasing the sweep frequency such that after a predetermined number of iterations, the sweep frequency increases or decreases from the sweep start frequency to the sweep end frequency.F. Determine from the records stored in memory the optimal frequency of the AC drive signal, which is the sweep frequency of the AC drive signal at which maximum active power is used by the ultrasound transducer.
G. The AC driver is controlled to output an AC drive signal to the ultrasonic transducer at an optimal frequency to drive the ultrasonic transducer and atomize the liquid.

In some examples, the active power monitoring arrangement comprises a current sensing arrangement for sensing a drive current of an alternating current drive signal driving the ultrasound transducer, and the active power monitoring arrangement comprises a monitoring signal indicative of the sensed drive current. I will provide a.

In some examples, the current sensing arrangement includes an analog-to-digital converter that converts the sensed drive current into a digital signal for processing by the processor.

In some examples, the memory stores, when executed by the processor, instructing the processor to repeat steps A through D in which the sweep frequency increases from a sweep start frequency of 2900 kHz to a sweep end frequency of 2960 kHz. ing.

In some examples, the memory stores, when executed by the processor, instructing the processor to repeat steps A through D in which the sweep frequency increases from a sweep start frequency of 2900 kHz to a sweep end frequency of 3100 kHz. ing.

In some examples, the memory, when executed by the processor, causes the processor to: in step G, output an AC drive signal to the ultrasound transducer at a frequency shifted by a predetermined shift amount from the optimal frequency; Stores instructions to control.

In some examples, the predetermined shift amount is between 1 and 10% of the optimal frequency.

In some examples, the battery is a 3.7V DC Li-Po battery.

In some examples, the driver device further includes a pressure sensor for sensing air flow along a driver device flow path extending through the driver device.

In some examples, the driver device further comprises a wireless communication system in communication with the processor, and the wireless communication system is configured to transmit and receive data between the driver device and the computing device.

In some examples, the driver device further comprises a driver device housing that is at least partially metal, the driver device housing housing the battery, the processor, the memory, the active power monitoring arrangement, and the AC driver, the driver device housing , including a recess for receiving and retaining a portion of the mist generator.

In some examples, the AC driver modulates the AC drive signal with pulse width modulation to maximize the active power being used by the ultrasound transducer.

It is noted that the expression "mist" used in the following disclosure means that the liquid is not heated as is usually done in conventional inhalers known from the prior art. In fact, conventional inhalers use heating elements to heat a liquid above its boiling temperature to generate vapor, which is different from a mist.

In fact, when a liquid is sonicated at high intensity, the sound waves propagating in the liquid medium produce alternating high pressure (compression) and low pressure (dilution) cycles at different speeds depending on the frequency. In a low-pressure cycle, high-intensity ultrasound waves create tiny vacuum bubbles or voids in the liquid. When these bubbles reach a volume that cannot absorb energy, they collapse violently under high-pressure cycles. This phenomenon is called cavitation. At this time, extremely high pressure is generated locally. Cavitation generates broken capillary waves that break the surface tension of a liquid and quickly release tiny droplets into the air in the form of a mist.

The cavitation phenomenon will be explained in more detail below.

When a liquid is atomized by ultrasonic vibration, fine water bubbles are generated in the liquid.

This bubble generation is a cavity formation process caused by negative pressure due to strong ultrasonic waves generated by the ultrasonic vibration means.

During positive pressure cycles, the cavity size becomes relatively small and negligible, and high-intensity ultrasound leads to rapid growth of the cavity.

Ultrasound, like other sound waves, consists of cycles of compression and expansion. Upon contact with a liquid, the compression cycle applies positive pressure to the liquid, forcing the molecules together. During the expansion cycle, negative pressure is applied and molecules are pulled apart from each other.

Strong ultrasound waves create areas of positive and negative pressure. Cavities may form and grow when there is negative pressure. When the cavity reaches a critical size, it collapses.

The amount of negative pressure required depends on the type and purity of the liquid. In the case of highly pure liquids, the tensile strength is so high that commercially available ultrasound generators cannot generate sufficient negative pressure to form cavities. For example, pure water requires a negative pressure of 1,000 atmospheres or more, but even the most powerful ultrasonic generator can only generate a negative pressure of about 50 atmospheres. The tensile strength of liquids is reduced by gases trapped in the interstices of liquid particles. This effect is similar to the strength loss caused by cracks in solid materials. When a negative pressure cycle is applied to a gas-filled gap by sound waves, the pressure drop causes the gas in the gap to expand, releasing small air bubbles into the solution.

However, the bubbles that are irradiated with ultrasound continue to absorb energy through alternating cycles of compression and expansion. As a result, the bubbles grow and contract repeatedly, maintaining a dynamic balance between the voids inside the bubbles and the liquid outside. Additionally, the size of bubbles may change due to ultrasound waves. Further, the average size of the bubbles may become large.

The growth of the cavity depends on the intensity of the sound. High-intensity ultrasound can rapidly expand the cavity during negative pressure cycles so that the cavity does not have a chance to contract during positive pressure cycles. In this way, the cavity can grow rapidly in one sound wave period.

For low-intensity ultrasound, the cavity size oscillates in phase with the expansion and compression cycles. The surface of the cavity created by low-intensity ultrasound is slightly larger during the expansion cycle than during the compression cycle. Since the amount of gas entering and exiting the cavity depends on the surface area, the diffusion into the cavity will be slightly greater during the expansion cycle than during the compression cycle. That is, for each period of sound, the cavity expands a little more than it contracts. As the process is repeated over and over again, the cavity slowly grows larger.

It has been found that the grown cavity eventually reaches a critical size at which it most efficiently absorbs ultrasound energy. This critical size depends on the ultrasound frequency. If the cavity grows too quickly due to high-intensity ultrasound, it can no longer efficiently absorb energy from the ultrasound. Without this energy input, the cavity can no longer sustain itself. The liquid rushes in and the cavity collapses due to a nonlinear response.

The energy released by the implosion breaks the liquid into tiny particles that are dispersed into the air as mist.

The equation describing the above nonlinear response phenomenon can be written as a "Rayleigh-Pleset" equation. This equation can be derived from the "Navier-Stokes" equation used in fluid mechanics.

Our approach is that the bubble volume V is the dynamic parameter and the physics describing the dissipation is the same as that used in the more classical form, where the radius is the dynamic parameter. was to rewrite the 'set' equation.

This equation is derived as follows:

In an ultrasonic atomizing inhaler, the liquid has a kinematic viscosity between 1.05 Pascal seconds and 1.412 Pascal seconds.

By solving the above equation with appropriate parameters for viscosity, density, and desired target bubble volume for liquid spray into air, we can calculate the range of liquid viscosity from 2.8 MHz to 3. It has been found that a frequency range of .2 MHz produces a bubble volume of about 0.25 microns to 0.5 microns.

The process of ultrasonic cavitation has a significant impact on the nicotine concentration in the generated mist.

Since no heating element is used, there is no burning of the heating element, and the effects of sidestream smoke can be reduced.

In some examples, the liquid comprises 57-70% (w/w) vegetable glycerin and 30-43% (w/w) propylene glycol, where the propylene glycol contains nicotine and optionally flavoring. include.

In an ultrasonic mist inhaler, a capillary element may extend between the sonication chamber and the liquid chamber.

In the ultrasonic mist inhaler, the capillary element is a material that is at least partially bamboo fiber.

The capillary element allows not only high absorption capacity and high absorption rate, but also high liquid retention.

The inherent properties of the proposed material used for the capillary tube were found to have a significant impact on the efficient functioning of the ultrasonic mist inhaler.

Furthermore, as an inherent characteristic of this material, it has good moisture absorption while maintaining good moisture permeability. This allows the aspirated liquid to penetrate into the capillary tube efficiently, and the high water absorbency allows it to retain a large amount of liquid, making the ultrasonic mist inhaler more effective than other products on the market. Now it can be used for a long time.

Another big advantage of using bamboo fiber is that it has antibacterial, antifungal, and deodorizing properties due to the naturally occurring antibacterial biological agent ``kun'' that is naturally present in bamboo fiber, making it suitable for medical applications. That is what we are doing.

This unique property of bamboo fibers has been verified through numerical analysis regarding the benefits of bamboo fibers in ultrasonic treatment.

The formula below has been tested on bamboo fiber materials for use as capillary elements and other materials such as cotton, paper, or other fiber strands, and bamboo fibers are much more suitable for use in sonication. Proven to have excellent properties:

In the ultrasonic mist inhaler, the capillary element can be a material that is at least partially bamboo fibre.

Further, in the ultrasonic mist inhaler, the material of the capillary element may be 100% bamboo fiber.

Extensive testing has concluded that 100% pure bamboo fiber is the most optimal choice for sonication.

In an ultrasonic mist inhaler, the material of the capillary element may be at least 75% bamboo fiber and optionally 25% cotton.

Capillary elements made from 100% pure bamboo fibers or a high proportion of bamboo fibers not only exhibit high absorption capacity but also have improved fluid permeability, which makes them the optimal choice for ultrasonic mist inhaler applications. .

In an ultrasonic mist inhaler, the capillary element may have a flat shape.

In an ultrasonic mist inhaler, the capillary element may consist of a central part and a peripheral part.

In the ultrasonic mist inhaler, the periphery may have an L-shaped cross section extending towards the liquid chamber.

In the ultrasonic mist inhaler, the central part may have a U-shaped cross section extending to the sonication chamber.

In an example ultrasonic mist inhaler, the liquid received in the liquid chamber includes 57-70% (w/w) vegetable glycerin and 30-43% (w/w) propylene glycol. , wherein the propylene glycol contains nicotine and fragrance.

Ultrasonic mist inhalers or personal ultrasonic atomization devices include:
a liquid reservoir structure comprising a liquid chamber or cartridge adapted to receive a liquid to be atomized; an ultrasonication chamber in fluid communication with said liquid chamber or said cartridge; said liquid received in said liquid chamber; It contains 57-70% (w/w) vegetable glycerin and 30-43% (w/w) propylene glycol, said propylene glycol containing nicotine and flavor.

In order to understand the invention more easily, embodiments of the invention will now be described by way of example with reference to the accompanying drawings:
FIG. 1 is an exploded perspective view of the components of an ultrasonic mist inhaler. FIG. 2 is an exploded perspective view of the components of the inhaler liquid reservoir structure. FIG. 3 is a cross-sectional view of the components of an inhaler liquid reservoir structure. FIG. 4A is an isometric view of the air flow member of the inhaler liquid reservoir structure according to FIGS. 2 and 3; FIG. 4B is a cross-sectional view of the blowing member shown in FIG. 4A. FIG. 5 is a schematic diagram showing a piezoelectric transducer modeled as an RLC circuit. FIG. 6 is a graph of frequency versus logarithmic impedance for an RLC circuit. FIG. 7 is a graph of frequency versus logarithmic impedance showing the inductive and capacitive regions of operation of a piezoelectric transducer. FIG. 8 is a flow diagram showing the operation of the frequency controller. FIG. 9 is a schematic perspective view of a mist inhaler of the present disclosure. FIG. 10 is a schematic perspective view of a mist inhaler of the present disclosure. FIG. 11 is a perspective perspective view of the mist generator of the present disclosure. FIG. 12 is a perspective perspective view of the mist generator of the present disclosure. FIG. 13 is a schematic exploded perspective view of the mist generator of the present disclosure. FIG. 14 is a perspective perspective view of a transducer holder of the present disclosure. FIG. 15 is a perspective perspective view of a transducer holder of the present disclosure. FIG. 16 is a perspective perspective view of a capillary element of the present disclosure. FIG. 17 is a perspective perspective view of a capillary element of the present disclosure. FIG. 18 is a perspective perspective view of a transducer holder of the present disclosure. FIG. 19 is a perspective perspective view of a transducer holder of the present disclosure. FIG. 20 is a schematic perspective view of a portion of a housing of the present disclosure. FIG. 21 is a perspective perspective view of an absorbent element of the present disclosure. FIG. 22 is a schematic perspective view of a portion of a housing of the present disclosure. FIG. 23 is a schematic perspective view of a portion of the housing of the present disclosure. FIG. 24 is a perspective perspective view of an absorbent element of the present disclosure. FIG. 25 is a schematic perspective view of a portion of a housing of the present disclosure. FIG. 26 is a schematic perspective view of a portion of a housing of the present disclosure. FIG. 27 is a schematic perspective view of a portion of a housing of the present disclosure. FIG. 28 is a schematic perspective view of a circuit board of the present disclosure. FIG. 29 is a schematic perspective view of a circuit board of the present disclosure. FIG. 30 is a schematic exploded perspective view of the mist generator of the present disclosure. FIG. 31 is a schematic exploded perspective view of the mist generator of the present disclosure. FIG. 32 is a cross-sectional view showing the mist generating device of the present disclosure. FIG. 33 is a cross-sectional view showing the mist generator of the present disclosure. FIG. 34 is a cross-sectional view showing the mist generator of the present disclosure. FIG. 35 is a perspective exploded perspective view of the driver device of the present disclosure. FIG. 36 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 37 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 38 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 39 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 40 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 41 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 42 is a perspective perspective view showing a portion of the driver device of the present disclosure. FIG. 43 is a schematic diagram of an integrated circuit arrangement of the present disclosure. FIG. 44 is a schematic diagram of an integrated circuit of the present disclosure. FIG. 45 is a schematic diagram of a pulse width modulation generator of the present disclosure. FIG. 46 is a timing diagram of an example of the present disclosure. FIG. 47 is a timing diagram of an example of the present disclosure. FIG. 48 is a table showing port functions in an example of the present disclosure. FIG. 49 is a schematic diagram of an integrated circuit of the present disclosure. FIG. 50 is a circuit diagram of an H bridge according to an example of the present disclosure. FIG. 51 is a circuit diagram of an example current sensing arrangement of the present disclosure. FIG. 52 is a circuit diagram of an H bridge according to an example of the present disclosure. FIG. 53 is a graph showing voltages between phases of operation of the H-bridge of FIG. 50. FIG. 54 is a graph showing voltages between phases of operation of the H-bridge of FIG. 50. FIG. 55 is a graph showing the voltage and current at the terminals of the ultrasonic transducer while the ultrasonic transducer is being driven by the H-bridge of FIG. 50. FIG. 56 is a schematic diagram showing connections between integrated circuits of the present disclosure. FIG. 57 is a schematic diagram of an integrated circuit of the present disclosure. FIG. 58 is a diagram for explaining steps of an authentication method according to an example of the present disclosure. FIG. 59 is a perspective perspective view of the end cap of the driver device of the present disclosure. FIG. 60 is a perspective perspective view of the housing of the driver device of the present disclosure. FIG. 61 is a graph showing the results of an EMC test on a mist inhaler of the present disclosure.

DETAILED DESCRIPTION Aspects of the present disclosure are best understood from the following detailed description when read in conjunction with the accompanying figures. Note that, in accordance with standard practice in the industry, the various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of discussion.

The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components, concentrations, uses, and arrangements are described below to simplify the disclosure. Of course, these are just examples and are not intended to be limiting. For example, attachment of a first feature and a second feature in the following description may include embodiments in which the first feature and the second feature are attached in direct contact; Embodiments may include embodiments in which additional features may be placed between the first feature and the second feature such that the two features may not be in direct contact. Additionally, this disclosure may repeat reference numbers and/or letters in various instances. This repetition is for simplicity and clarity, and as such does not imply a relationship between the various embodiments and/or configurations discussed.

The following disclosure describes representative examples. Each example may be considered an embodiment, and in this disclosure, references to "example" may be changed to "embodiment."

Some portions of this disclosure are directed to electronic vaporizing inhalers. Specific examples described below include nicotine. However, other examples are also envisioned, such as inhalers for therapeutic agents, medicines, and herbal supplements. Additionally, the device can be packaged to look like a medical device that does not resemble a cigarette.

Ultrasonic mist inhalers are either disposable or reusable. The term "reusable" as used herein means that the energy storage device is rechargeable or replaceable, or that the liquid can be replenished either by refilling or replacing the liquid reservoir structure. means. Alternatively, in some instances, reusable electronic devices are both rechargeable and capable of being refilled with liquid.

Conventional electronic vaporizing inhalers tend to rely on inducing high temperatures in metal parts that are configured to heat the liquid within the inhaler, thus vaporizing the liquid that can be inhaled. The liquid typically contains nicotine and flavoring blended in a solution of propylene glycol (PG) and vegetable glycerin (VG), which are vaporized via heating elements at high temperatures. The problem with traditional inhalers is that the metal can burn, which can then be inhaled along with the burned liquid. Additionally, some people do not like the burnt smell and taste of heated liquids.

1 to 4 are diagrams showing an example of an ultrasonic inhaler constituting an ultrasonic processing chamber.

In FIG. 1, a disposable ultrasonic mist inhaler 100 is depicted. As can be seen from FIG. 1, the ultrasonic mist inhaler 100 has a cylindrical body whose length is relatively long compared to its diameter. In the disposable example, the first part and the second part are regions of a single, but separable device. The names 1st part 101 and 2nd part 102 are used to conveniently distinguish the components mainly included in each part.

As can be seen from FIG. 1, the ultrasonic mist inhaler is composed of a mouthpiece 1, a reservoir structure 2, and a casing 3. The first part 101 constitutes the casing 3, and the second part 102 constitutes the mouthpiece 1 and the reservoir structure 2.

The first portion 101 contains power supply energy.

Power storage device 30 supplies power to ultrasonic mist inhaler 100 . The power storage device 30 can be, but is not limited to, a battery such as a lithium ion battery, an alkaline battery, a zinc-carbon battery, a nickel-metal hydride battery, a nickel-cadmium battery, a supercapacitor, or a combination thereof. do not have. In disposable examples, electrical storage device 30 is not rechargeable, while in reusable examples, electrical storage device 30 would be selected to be rechargeable. In the disposable example, the electrical storage device 30 is primarily selected to provide a constant voltage over the life of the inhaler 100. Otherwise, the performance of the inhaler will deteriorate over time. Preferred electrical storage devices that can provide a constant voltage output over the life of the device include lithium ion batteries and lithium polymer batteries.

Electricity storage device 30 has a first end 30a that generally corresponds to a positive terminal and a second end 30b that generally corresponds to a negative terminal. The negative terminal extends to the first end 30a.

Since the power storage device 30 is located in the first part 101 and the liquid reservoir structure 2 is located in the second part 102, a joint is necessary to provide electrical communication between these components. . In the present invention, electrical communication is established using at least electrodes or probes that are compressed together when the first part 101 is clamped onto the second part 102.

In this example, power storage device 30 is rechargeable in order to be reusable. A charging port 32 is provided in the casing 3.

Integrated circuit 4 has a proximal end 4a and a distal end 4b. The positive terminal of the first end 30a of the electricity storage device 30 is in electrical communication with the positive lead of the flexible integrated circuit 4. The negative terminal of the second end 30b of the electrical storage device 30 is in electrical communication with the negative lead of the integrated circuit 4. The distal end 4b of the integrated circuit 4 is configured to include a microprocessor. The microprocessor processes data from the sensor, controls the lights, directs the flow of current to the ultrasonic vibrations 5 in the second portion 102, and terminates the flow of current after a preprogrammed time. It is configured.

The sensor detects when the ultrasonic mist inhaler 100 is in use (when the user inhales the inhaler) and activates the microprocessor. Sensors can be selected to detect changes in pressure, airflow, or vibration. In one example, the sensor is a pressure sensor. In digital devices, the sensor takes continuous readings, and as a result, the digital sensor needs to draw current continuously, but the amount is small and the overall battery life will be negligibly affected.

In some examples, integrated circuit 4 constitutes an H-bridge that may be formed by four MOSFETs to convert direct current to alternating current at high frequencies.

Referring to FIGS. 2 and 3, an illustration of a liquid reservoir structure 2 according to an example is shown. The liquid reservoir structure 2 consists of a liquid chamber 21 adapted to receive the liquid to be atomized and an ultrasound treatment chamber 22 in fluid communication with the liquid chamber 21.

In the example shown, the liquid reservoir structure 2 comprises an inlet channel 20 providing an air passage from the sonication chamber 22 towards the environment.

As an example of a sensor location, a sensor may be placed in the ultrasonic processing chamber 22.

The suction channel 20 has a conical portion 20a and an inner container 20b.

As depicted in FIGS. 4A and 4B, the suction channel 20 further includes an air flow member 27 for supplying air flow to the sonication chamber 22 from the surroundings.

The airflow member 27 has an airflow bridge 27a and an airflow duct 27b made in one piece, the airflow bridge 27a having two airway openings 27a' forming part of the suction channel 20, and the airflow duct 27b forming an airflow bridge 27b. 27a into the sonication chamber 22 to provide air flow from the surroundings to the sonication chamber.

The airflow bridge 27a cooperates with the conical element 20a at the second diameter 20a2.

Airflow bridge 27a has two opposing peripheral openings 27a'' that supply airflow to airflow duct 27b.

The cooperation of the airflow bridge 27a and the frustoconical element 20a is arranged such that two opposing peripheral openings 27a'' cooperate with complementary openings 20a'' of the frustoconical element 20a.

The base 1 and the conical part 20a are spaced apart from each other in the radial direction, and an airflow chamber 28 is arranged therebetween.

As depicted in FIGS. 1 and 2, the mouthpiece 1 has two opposing peripheral openings 1''.

The peripheral openings 27a'', 20a'', 1'' of the airflow bridge 27a, the frustoconical element 20a and the mouthpiece 1 provide maximum airflow directly into the sonication chamber 22.

The conical element 20a includes an internal passage aligned in a similar direction to the suction channel 20, the first diameter 20a1 being smaller than that of the second diameter 20a2, the internal passage decreasing in diameter across the conical element 20a. It has an internal passageway to allow it.

The conical element 20a is arranged in alignment with the ultrasonic vibration means 5 and the capillary element 7, with a first diameter 20a1 communicating with the internal duct 11 of the mouthpiece 1 and a second diameter 20a2 communicating with the internal container 20b. are doing.

The inner container 20b has an inner wall that partitions the ultrasonic processing chamber 22 and the liquid chamber 21.

The liquid reservoir structure 2 has an outer container 20c that defines an outer wall of the liquid chamber 21.

Inner container 20b and outer container 20c are the inner wall and outer wall of liquid chamber 21, respectively.

The liquid reservoir structure 2 is arranged between the cap 1 and the casing 3 and is removable from the cap 1 and the casing 3.

The liquid reservoir structure 2 and the mouthpiece 1 or casing 3 may include a complementary arrangement for engaging each other; further such complementary arrangement may include a bayonet arrangement; a threaded arrangement; a magnetic arrangement. or a friction-fit arrangement, with the liquid reservoir structure 2 comprising one part of the arrangement and the mouthpiece 1 or casing 3 comprising a complementary part of the arrangement.

In reusable examples, the components are substantially the same. The difference in reusable versus disposable examples is the accommodation made for replacing the liquid reservoir structure 2.

As shown in FIG. 3, the liquid chamber 21 has a top wall 23 and a bottom wall 25 that close an inner container 20b and an outer container 20c of the liquid chamber 21. As shown in FIG.

The capillary element 7 is arranged between the first part 20b1 and the second part 20b2 of the inner container 20b.

The capillary element 7 has a flat shape extending from the sonication chamber to the liquid chamber.

As depicted in FIG. 2 or 3, the capillary element 7 consists of a U-shaped central part 7a and an L-shaped peripheral part 7b.

The L-shaped portion 7b extends along the bottom wall 25 into the liquid chamber 21 on the inner container 20b.

The U-shaped portion 7a is housed within the ultrasonic processing chamber 21. The U-shaped portion 7a is provided along the bottom wall 25 on the inner container 20b.

In the ultrasonic atomization inhaler, the U-shaped portion 7a has an inner portion 7a1 and an outer portion 7a2, the inner portion 7a1 is in surface contact with the atomization surface 50 of the ultrasonic vibration means 5, and the outer portion 7a2 is not in surface contact with the ultrasonic vibration means 5.

The bottom wall 25 of the liquid chamber 21 is a bottom plate 25 that closes off the liquid chamber 21 and the ultrasonic processing chamber 22 . Since the bottom plate 25 is sealed, leakage of liquid from the ultrasonic processing chamber 22 to the casing 3 is prevented.

The bottom plate 25 has an upper surface 25a having a recess 25b into which the elastic member 8 is inserted. The ultrasonic vibration means 5 is supported by an elastic member 8. The elastic member 8 is formed of an annular plate-shaped rubber having an inner hole 8' in which a groove for holding the ultrasonic vibration means 5 is designed.

The upper wall 23 of the liquid chamber 21 is a cap 23 that closes the liquid chamber 23.

Top wall 23 has an upper surface 23 representing the maximum level of liquid that liquid chamber 21 can contain and a lower surface 25 representing the minimum level of liquid within liquid chamber 21 .

Since the top wall 23 is sealed, leakage of liquid from the liquid chamber 21 to the cap 1 is prevented.

The top wall 23 and the bottom wall 25 are fixed to the liquid reservoir structure 2 by fixing means such as screws, adhesive, friction, or the like.

As depicted in Figure 3, the elastic member is in line contact with the ultrasonic vibration means 5 and prevents contact between the ultrasonic vibration means 5 and the wall of the inhaler, thereby reducing the vibration of the liquid reservoir structure. Suppression is more effectively prevented. Therefore, the fine particles of the liquid atomized by the atomization member can be atomized further.

As depicted in FIG. 3, the inner container 20b has an opening 20b' between the first part 20b1 and the second part 20b2, through which the capillary element 7 extends from the sonication chamber 21. There is. Capillary element 7 absorbs liquid from liquid chamber 21 via opening 20b'. Capillary element 7 is a wick. The capillary element 7 transports the liquid to the sonication chamber 22 by capillary action. In some examples, capillary element 7 is made of bamboo fiber. In some examples, capillary element 7 may be between 0.27 mm and 0.32 mm thick and have a density between 38 g/m ² and 48 g/m ² .

As can be seen in FIG. 3, the ultrasonic vibration means 5 are arranged directly below the capillary element 7.

The ultrasonic vibration means 5 may be a transducer. For example, the ultrasonic vibration means 5 may be a piezoelectric transducer or may be designed in the shape of a circular plate. The material of the piezoelectric transducer may be ceramic.

Moreover, various transducer materials can be used for the ultrasonic vibration means 5.

The end of the blower duct 27b1 faces the ultrasonic vibration means 5. The ultrasonic vibration means 5 is in electrical communication with the electrical contactors 101a, 101b. Note that the distal end 4b of the integrated circuit 4 has an inner electrode and an outer electrode. The inner electrode contacts a first electrical contact 101a, which is a spring contact probe, and the outer electrode contacts a second electrical contact 101b, which is a side pin. Through the integrated circuit 4, the first electrical contact 101a electrically communicates with the positive terminal of the power storage device 30 via the microprocessor, and the second electrical contact 101b electrically communicates with the negative terminal of the power storage device 30. are doing.

Electrical contacts 101a, 101b cross the bottom plate 25. The bottom plate 25 is adapted to be received inside the peripheral wall 26 of the liquid reservoir structure 2 . Bottom plate 25 rests on complementary ridges, thereby forming liquid chamber 21 and sonication chamber 22.

The inner container 20b consists of a circular inner slot 20d to which a mechanical spring is applied.

By pressing the central part 7a1 against the ultrasonic vibration means 5, the mechanical spring 9 ensures a contact surface between them.

Liquid reservoir structure 2 and base plate 25 can be made using a variety of thermoplastic materials.

When the user inhales the ultrasonic mist inhaler 100, airflow is drawn through the peripheral opening 1'', through the airflow chamber 28, through the peripheral opening 27a'' of the airflow bridge 27a and through the frustoconical element 20a. , flows down into the sonication chamber 22 via the airflow duct 27b and directly onto the capillary element 7. At the same time, liquid is drawn from the reservoir chamber 21 through the plurality of openings 20b' into the capillary element 7 by capillary action. The capillary element 7 brings the liquid into contact with the ultrasonic vibration means 5 of the inhaler 100. In addition, the pressure sensor activates the integrated circuit 4 by the user's suction, and the integrated circuit 4 conducts a current to the ultrasonic vibration means 5. Thus, when the user inhales with the mouthpiece 1 of the inhaler 100, two actions occur simultaneously. First, the sensor activates the integrated circuit 4, which triggers the ultrasonic vibration means 5 to start vibrating. Second, the suction reduces the pressure outside the reservoir chamber 21 such that a flow of liquid through the opening 20b' is initiated, which saturates the capillary element 7. The capillary element 7 conveys the liquid to the ultrasonic vibration means 5, which causes bubbles to be formed in the capillary channel and the liquid to become a mist. Then, the user sucks the misted liquid.

In some examples, integrated circuit 4 includes a frequency controller configured to control the frequency at which ultrasonic vibration means 5 operates. The frequency controller includes a processor and a memory storing executable instructions that, when executed by the processor, cause the processor to perform at least one function of the frequency controller.

As mentioned above, in some examples, the ultrasonic mist inhaler 100 may be configured to absorb a liquid of 1.05 Pa·s to 1.412 Pa·s to produce a bubble volume of approximately 0.25 to 0.5 microns. In order to vaporize a viscous liquid, the ultrasonic vibration means 5 is driven with a signal having a frequency of 2.8 MHz to 3.2 MHz. However, for liquids with different viscosities or other applications, it is possible that the ultrasonic vibration means 5 are driven at different frequencies.

For each different application of the mist generator, there is an optimum frequency or frequency range for driving the ultrasonic vibration means 5 to optimize the mist generation. In the example where the ultrasonic vibration means 5 is a piezoelectric transducer, the optimum frequency or frequency range will depend on at least the following four parameters:

1. Manufacturing process of the transducer In some examples, the ultrasonic vibration means 5 consists of a piezoelectric ceramic. Piezoelectric ceramics are manufactured by mixing compounds to create a ceramic fabric, but this mixing process may not be consistent throughout manufacturing. This non-uniformity can cause variations in the resonant frequency of the cured piezoelectric ceramic.

If the resonant frequency of the piezoelectric ceramic does not correspond to the required operating frequency of the device, no mist will be produced during operation of the device. In the case of therapeutic mist inhalers, even a slight shift in the piezoceramic's resonant frequency can affect the mist production, meaning that the device will not be able to provide an adequate therapeutic level to the user.

2. Load on the Transducer During operation, when the load on the piezoelectric transducer changes, the vibration displacement of the entire piezoelectric transducer is suppressed. To optimally displace the piezoelectric transducer's vibrations, the drive frequency must be adjusted so that the circuit can provide sufficient power for maximum displacement.

Types of loads that affect oscillator efficiency include the amount of liquid on the transducer (humidity of the wicking material), the spring force applied to the wicking material to maintain permanent contact with the transducer, etc. be able to. It may also include electrical connection means.

3. Temperature The ultrasonic vibrations of the piezoelectric transducer are partially damped by incorporating it into the device. This could be done by placing the transducer in a silicone/rubber ring and using a spring to apply pressure to the wicking material above the transducer. This damping of vibrations increases the local temperature above and around the transducer.

An increase in temperature affects the vibrations due to changes in the molecular behavior of the transducer. The increase in temperature gives more energy to the ceramic's molecules and temporarily affects its crystal structure. This effect reverses as the temperature decreases, but modulation of the applied frequency is necessary to maintain optimal oscillation. This frequency modulation could not be achieved with conventional fixed frequency devices.

Furthermore, since the viscosity of the vaporized solution (e-liquid) decreases due to the temperature increase, it may be necessary to change the driving frequency in order to induce cavitation and maintain continuous mist generation. For conventional fixed frequency devices, reducing the viscosity of the liquid without changing the drive frequency reduces or completely stops mist production, rendering the device inoperable.

4. Distance to power supply The oscillation frequency of an electronic circuit may vary depending on the length of the wiring between the transducer and the oscillator-driver. The frequency of an electronic circuit is inversely proportional to the distance between the transducer and the rest of the circuit.

Although the distance parameter is primarily fixed to the device, it can change during the device manufacturing process and reduce the overall efficiency of the device. Therefore, it is desirable to change the driving frequency of the device to compensate for the variations and optimize the efficiency of the device.

A piezoelectric transducer can be modeled as an RLC circuit in an electronic circuit, as shown in FIG. The four parameters mentioned above can be modeled as changes in the inductance, capacitance, and resistance of the entire RLC circuit, which can change the resonant frequency range delivered to the transducer. As the frequency of the circuit increases to near the resonance of the transducer, the logarithmic impedance of the entire circuit drops to a minimum, then rises to a maximum before settling in the middle range.

FIG. 6 is a general graph illustrating the change in overall impedance with increasing frequency in an RLC circuit. FIG. 7 shows how the piezoelectric transducer acts as a capacitor in the first capacitive region at frequencies below the first predetermined frequency f _s and in the second capacitive region at frequencies above the second predetermined frequency f _p FIG. The piezoelectric transducer acts as an inductor in the inductive region at frequencies between the first and second predetermined frequencies _fs , _fp . In order to maintain optimal oscillation of the transducer and thus obtain maximum efficiency, it is necessary to maintain the current flowing through the transducer at a frequency within the inductive region.

The frequency controller of some example devices is configured to maintain the oscillation frequency of the piezoelectric transducer (ultrasonic vibration means 5) within the induction region in order to maximize the efficiency of the device.

The frequency controller is configured to perform a sweep operation that drives the transducer at a frequency that tracks progressively over a predetermined sweep frequency range. When the frequency controller performs a sweep, the frequency controller monitors the analog-to-digital conversion (ADC) value of an analog-to-digital converter coupled to the transducer. In some examples, the ADC value is a parameter of the ADC that is proportional to the voltage across the transducer. In other examples, the ADC value is a parameter of the ADC that is proportional to the current flowing through the transducer.

As described in more detail below, the frequency controller in some examples determines the active power being used by the ultrasound transducer by monitoring the current flowing through the transducer.

During the sweep operation, the frequency controller searches for a guiding region of frequency for the transducer. Once the frequency controller identifies the induction region, the frequency controller records the ADC value and adjusts the drive frequency of the transducer to the frequencies within the induction region (i.e., the first and second (between predetermined frequencies f _s and f _p ). When the drive frequency is locked within the inductive region, the electromechanical coupling coefficient of the transducer is maximized, thereby maximizing the efficiency of the device.

In some examples, the frequency controller is configured to perform a sweeping operation to locate the induction region each time oscillation is initiated or restarted. In the example, the frequency controller is configured to lock the drive frequency at a new frequency within the induction region each time oscillation is initiated, thereby compensating for changes in parameters that affect the operating efficiency of the device. .

In some examples, the frequency controller ensures optimal mist production and maximizes the efficiency of drug delivery to the user. In some examples, the frequency controller optimizes the device to improve efficiency and maximize therapy delivery to the user.

In other examples, the frequency controller optimizes the device and improves the efficiency of any other device that uses ultrasound. In some examples, the frequency controller is configured for use with ultrasound technology for therapeutic applications to enhance enhanced drug release from ultrasound-responsive drug delivery systems. Having a precise and optimal frequency during operation ensures that microbubbles, nanobubbles, nanodroplets, liposomes, emulsions, micelles, or any other delivery system is highly effective.

In some examples, the frequency controller is configured to operate in a recursive mode to ensure optimal mist production and optimal delivery of compounds as described above. When the frequency controller operates in recursive mode, the frequency controller performs periodic frequency sweeps during device operation and monitors the ADC value until the ADC value is above a predetermined threshold indicating optimal oscillation of the transducer. Determine whether it exists or not.

In some examples, the frequency controller performs a sweep operation while the device is in the process of aerosolizing the liquid in case the frequency controller can identify a possible better frequency for the transducer. If the frequency controller identifies a better frequency, the frequency controller locks the drive frequency at the newly identified better frequency to maintain optimal operation of the device.

In some examples, the frequency controller performs a frequency sweep for a predetermined duration periodically during operation of the device. For the example device described above, the predetermined duration of the sweeps and the time periods between sweeps are selected to optimize the functionality of the device. When implemented in an ultrasonic mist inhaler, this ensures optimal delivery to the user throughout his or her inhalation.

FIG. 8 is a flow diagram of the operation of some example frequency controllers.

The following disclosure discloses further examples of mist inhalers that consist of many of the same elements as the examples described above. Elements of the examples described above may be replaced with any of the elements of the examples described in the remainder of this disclosure.

To ensure sufficient aerosol production, in this example the mist inhaler consists of an ultrasonic/piezoelectric transducer with a diameter of exactly or substantially 16 mm. The transducer is manufactured to specific capacitance and impedance values to control the frequency and power required to produce the desired amount of aerosol.

If a disk-shaped ultrasonic transducer with a diameter of 16 mm is placed horizontally, the device becomes large and may be ergonomically disadvantageous as a hand-held device. To alleviate this concern, the ultrasonic transducer in this example is held vertically within the sonication chamber (the plane of the ultrasonic transducer is generally parallel to the flow of the aerosol mist into the mouthpiece, and and/or generally parallel to the longitudinal length of the mist inhaler). Stated another way, the ultrasound transducer is generally perpendicular to the base of the mist inhaler.

Referring now to FIGS. 9 and 10 of the accompanying drawings, some example mist inhalers 200 are comprised of a mist generator 201 and a driver device 202. In this example, the driver device 202 includes a recess 203 that receives and holds a part of the mist generator 201. Therefore, the mist generator 201 can be combined with the driver device 202 to form a compact and portable mist inhaler 200, as shown in FIG.

Referring now to Figures 11-13 of the accompanying drawings, the mist generator 201 is comprised of a mist generator housing 204 that is elongated and formed from two housing parts 205, 206 that are optionally attached to each other. Mist generator housing 204 is comprised of an air inlet port 207 and a mist outlet port 208.

In this example, the mist generator housing 204 is injection molded plastic, specifically polypropylene typically used in medical applications. In this example, the mist generator housing 204 is a heterophasic copolymer. More specifically, it is a BF970MO heterophasic copolymer with an optimal combination of very high stiffness and high impact strength. Mist generator housing parts molded from this material exhibit good antistatic performance.

A heterophasic copolymer such as polypropylene is particularly suitable for the mist generator housing 204 because this material does not cause aerosol condensation as it flows from the sonication chamber 219 through the mouthpiece to the user. This plastic material can also be easily recycled directly using industrial crushing and cleaning processes.

In FIGS. 9, 10 and 12, the mist outlet port 208 is closed by a closure element 209. In FIGS. However, it will be appreciated that during use of the mist inhaler 200, the closure element 209 is removed from the mist outlet port 208, as shown in FIG.

Referring now to FIGS. 14 and 15, the mist generator 200 includes a transducer holder 210 held within the mist generator housing 204. In this example, the transducer holder 210 includes a cylindrical or generally cylindrical main body 211 and upper and lower circular openings 212 and 213. Transducer holder 210 is provided with an internal channel 214 for receiving the end of ultrasound transducer 215, as shown in FIG.

The transducer holder 210 incorporates a cutout 216 through which an electrode 217 extends from the ultrasound transducer 215 so that the electrode 217 can be electrically connected to an AC driver of the driver device, as described in more detail below. 217 extends from the ultrasound transducer 215.

Referring again to FIG. 13, the mist generator 201 includes a liquid chamber 218 provided within the mist generator housing 204. Liquid chamber 218 is for containing a liquid, such as a therapeutic liquid, to be atomized. In some examples, liquid is contained in liquid chamber 218. In other examples, liquid chamber 218 is initially empty and then the liquid chamber is filled with liquid.

Preferably, the liquid includes at least one therapeutic agent suitable for aerosol delivery to the lungs through inhalation by the patient to provide the desired treatment to the patient. Some examples of therapeutic agents include, but are not limited to, aerosol delivery of pharmaceutical agents to the lungs to promote systemic or direct clinical effects while producing minimal side effects. . Therapeutic agents also include, for example, natural drugs, cannabinoid derivatives such as CBD for pain relief and other treatments, botanical drugs, opioids, RNA, DNA, chemotherapy, cells containing e.g. ribosomes, endoplasmic reticulum, cytoskeleton and mitochondria. Ingredients, supplements to improve performance (drugs such as albuterol/salbutamol for asthma patients, β-lactams, polymyxins, aminoglycoside antibacterial antibiotics, amphotericin B, morphine, fentanyl, prostacyclin, amiloride, interferon G, lung transplant patients) Rescue therapy for cancer may include, but is not limited to, cyclosporine as a treatment for rejection and asthma.

Although the following description refers to nicotine, in other examples of this disclosure, nicotine is replaced with, but not limited to, one or more of the therapeutic agents described herein.

A liquid (herein also referred to as e-liquid) consisting of a nicotine salt consisting of nicotine levulinate, suitable for use in ultrasound equipment powered by a 3.7 V lithium polymer (LiPo) battery at a frequency of 3.0 MHz (±0.2 MHz). (called) composition, which is:
The relative amount of vegetable glycerin in the composition is: 55 to 80% (w/w), or 60 to 80% (w/w), or 65 to 75% (w/w), or 70% (w/w). w), and/or the relative amount of propylene glycol in the composition is: 5-30% (w/w), or 10-30% (w/w), or 15-25% (w/w), or 20% (w/w), and/or the relative amount of water in the composition is: 5 to 15% (w/w), or 7 to 12% (w/w), or 10% (w/w) , and/or the amount of nicotine and/or nicotine salt in the composition is: 0.1 to 80 mg/ml, or 0.1 to 50 mg/ml, or 1 to 25 mg/ml, or 10 to 20 mg/ml, or 17mg/ml.

In some examples, the mist generator 201 contains an electronic liquid having a kinematic viscosity between 1.05 Pascal·seconds and 1.412 Pascal·seconds.

In some examples, liquid chamber 218 contains a liquid that includes nicotine levulinate salt in a 1:1 molar ratio.

In some examples, liquid chamber 218 includes a liquid having a kinematic viscosity between 1.05 Pascal seconds and 1.412 Pascal seconds and a liquid density between 1.1 g/ml and 1.3 g/ml. .

By using an e-liquid with the correct parameters of viscosity, density and having the desired target bubble volume of the liquid spray in the air, the liquid viscosity ranges from 1.05 Pa·sec to 1.412 Pa·sec and approx. A frequency of 2.8 MHz to 3.2 MHz for a density of .1 to 1.3 g/mL (density range taken from Hertz) means that 90% of the droplets are less than 1 micron and 50% of them are less than 0.5 micron. It has been shown to produce a droplet volume of .

The mist generator 201 includes an ultrasonic treatment chamber 219 provided within the mist generator housing 204.

Returning to FIGS. 14 and 15, the transducer holder 210 is configured to include a partition 220 that provides a barrier between the liquid chamber 218 and the sonication chamber 219. The barrier provided by partition portion 220 minimizes the risk of sonication chamber 219 flooding with liquid from liquid chamber 218 or oversaturating the capillary element on ultrasound transducer 215, either of which Overloading the transducer 215 and reducing its efficiency. Additionally, flooding the sonication chamber 219 or oversaturating the capillary elements may also cause the user to experience an unpleasant experience of inhaling liquid during inhalation. To reduce this risk, the partition portion 220 of the transducer holder 210 sits as a wall between the sonication chamber 219 and the liquid chamber 218.

The partition 220 constitutes a capillary opening 221 that is the only means by which liquid can flow from the liquid chamber 218 to the sonication chamber 219 via the capillary element. In this example, capillary opening 221 is an elongated slot having a width of 0.2 mm to 0.4 mm. The dimensions of the capillary opening 221 are such that the edges of the capillary opening 221 provide a biasing force acting on the capillary tube extending through the capillary opening 221 to add control of liquid flow to the sonication chamber 219. .

In this example, transducer holder 210 is liquid silicone rubber (LSR). In this example, the liquid silicone rubber has a hardness of 60 Shore A. The LSR material ensures that the ultrasound transducer 215 vibrates without the transducer holder 210 damping the vibrations. In this example, the vibrational displacement of the ultrasound transducer 215 is between 2 and 5 nanometers, and any damping effect may reduce the efficiency of the ultrasound transducer 215. Therefore, the material and hardness of this LSR are selected for optimal performance with minimal compromise.

16 and 17, the mist generating device 201 includes a capillary tube or capillary element 222 for transferring liquid (containing drugs or other substances) from the liquid chamber 218 to the sonication chamber 219. There is. The tube element 222 is planar or generally planar with a first portion 223 and a second portion 224 . In this example, first portion 223 has a rectangular or generally rectangular shape and second portion 224 has a partially circular shape.

In this example, the capillary element 222 is comprised of a third portion 225 and a fourth portion 226, each having the same shape as the first and second portions 223, 224. The capillary element 222 in this example is centered around a fold line 227 such that the first and second portions 223, 224 and the third and fourth portions 225, 226 are superimposed on each other, as shown in FIG. Folded.

In this example, the capillary element has a thickness of approximately 0.28 mm. When the capillary element 222 is folded to have two layers, as shown in FIG. 17, the total thickness of the capillary element is approximately 0.56 mm. This double layer also ensures that there is always sufficient liquid on the ultrasound transducer 215 for optimal aerosol production.

In this example, when the capillary element 222 is collapsed, the lower ends of the first and third portions 223, 225 are located in the liquid in the liquid chamber 218 to maximize the rate at which the capillary element 222 absorbs liquid. A portion of capillary element 222 defines an enlarged lower end 228 that increases the surface area.

In this example, capillary element 222 is 100% bamboo fiber. In other examples, the capillary element is at least 75% bamboo fiber. The advantages of using bamboo fibers as capillary elements have been mentioned above.

18 and 19, the capillary element 222 is attached to the transducer holder such that the transducer holder 210 retains a second portion 224 of the capillary element 222 overlapping a portion of the atomizing surface of the ultrasound transducer 215. 210. In this example, the circular second portion 224 fits within the inner recess 214 of the transducer holder 210.

A first portion 223 of capillary element 222 extends through capillary opening 221 of transducer holder 210 .

20-22, the second portion 206 of the mist generator housing 204 consists of a generally circular wall 229 that receives the transducer holder 222 and forms part of the wall of the sonication chamber 219.

Contact openings 230 and 231 are provided in the side walls of second portion 206 for receiving electrical contacts 232 and 233 that form electrical connections with the electrodes of ultrasound transducer 215.

In this example, an absorbent tip or element 234 is provided adjacent the mist outlet port 208 to absorb liquid at the mist outlet port 208 . In this example, absorbent element 234 is of bamboo fiber.

23-25, a first portion 205 of the mist generator housing 204 is of similar shape to the second portion 206 and forms a further portion of the wall of the sonication chamber 219 and includes a transducer holder. It further includes a generally circular wall 235 that retains 210 .

In this example, an absorbent element 236 is further provided adjacent to the mist outlet port 208 for absorbing liquid at the mist outlet port 208.

In this example, the first portion 205 of the mist generator housing 204 defines a spring support arrangement 237 that supports the lower end of a retainer spring 238, as shown in FIG.

The upper end of retainer spring 238 contacts second portion 224 of capillary element 222 such that retainer spring 238 provides a biasing force that biases capillary element 222 against the atomizing surface of ultrasound transducer 215 .

Referring to FIG. 27, before the two parts 205, 206 of the mist generator housing 204 are attached to each other, the transducer holder 210 is in place and held by the second part 206 of the mist generator housing 204. It is shown that there is.

Referring to FIGS. 28 to 31, in this example, mist generator 201 is configured to include an identification array 239. The identification arrangement 239 consists of a printed circuit board 240 with electrical contacts 241 on one side, an integrated circuit 242 and further optional components 243 on the other side.

Integrated circuit 242 has a memory that stores an identifier unique to mist generator 201 . Electrical contacts 241 provide an electronic interface for communicating with integrated circuit 242.

A printed circuit board 240 is mounted within a recess 244 in one side of the mist generator housing 204 in this example. Integrated circuit 242 and any other electronic components 243 are seated within further recess 245 such that printed circuit board 240 is generally flush with the sides of mist generator housing 204 .

In this example, integrated circuit 242 is a one-time programmable (OTP) device, which is an anti-counterfeit feature that allows only genuine mist generators from the manufacturer to be used with the device. This anti-counterfeiting feature is implemented in the mist generator 201 as a specific custom integrated circuit (IC) that is adhered to the mist generator 201 (with the printed circuit board 240). The OTP as an IC contains truly unique information that allows full traceability of the mist generator 201 (and its contents) over its lifetime, as well as accurate monitoring of consumption by the user. The OTP IC allows the mist generator 201 to function to generate mist only when authorized.

An example OTP IC implementation of the present disclosure will be described in detail below.

The OTP characteristically defines the authorized status of a particular mist generating device 201. In fact, in order to prevent carbonyl emissions and keep the aerosol at a safe level, experiments have shown that after approximately 1000 seconds of aerosolization, the mist generator 201 considers the liquid in the liquid chamber 218 to be empty. has been done. As such, a non-genuine or empty mist generator 201 cannot be operated after this predetermined usage time.

The OTP as a feature may be part of a complete chain of cooperation between the digital sale point, the mobile companion application, and the mist generator 201. Only genuine mist generators 201 manufactured by trusted parties and sold at digital sale points may be used. The mobile companion digital app is a link between the user account on the manufacturer's digital platform and the mist generator 201, ensuring safe use of known safe content with a safe amount of puff duration. It is something to do.

OTP as a function also enables high access control and monitoring required for medical drug administration in case of B2B (business to business) use with trusted medical facilities. The OTP IC is read by a driver device 202 that is able to recognize the inserted mist generating device 201 and its associated prescription. The driver device 202 cannot use the mist generating device 201 for a period longer than or outside the period designated by the prescription. Furthermore, by providing reminders on a mobile companion app, users can minimize missed doses.

In some examples, the OTP IC, like the mist generator 201, is disposable. Whenever the mist generator 201 is considered empty, it will not be activated if inserted into the driver device 202. Similarly, a counterfeit generator device 201 will not function in the driver device 202.

32 to 34 are diagrams showing how air flows inside the mist generating device 201 during operation.

Liquid therapeutic agents (medical solutions, medical suspensions, protein solutions, supplements, etc.) are transformed into mist (aerosolization) by ultrasonication. However, this mist will settle onto the ultrasound transducer 215 unless sufficient ambient air is available to displace the rising aerosol. In the ultrasonic treatment chamber 219, a continuous supply of air is required because a mist (aerosol) is generated and drawn out to the user via the mouthpiece. To meet this requirement, air channels are provided. In this example, the airflow channels have an average cross-sectional area of 11.5 mm ² , which is calculated and designed into the sonication chamber 219 based on the negative pressure from an average user. This also controls the mist-to-air ratio of the inhaled aerosol and controls the amount of drug delivered to the user.

Based on design requirements, the air flow path is routed starting at the bottom of the sonication chamber 219. The opening in the bottom of the aerosol chamber is aligned with and closely adjacent the opening to the airflow bridge within the device. The air flow path runs vertically upward along the reservoir and continues to the center of the sonication chamber (concentric with the ultrasound transducer 215). Now turn inward 90 degrees. The flow path then continues approximately 1.5 mm from the ultrasound transducer 215. This path maximizes the supply of ambient air directly in the direction of the atomization surface of the ultrasonic transducer 215. Air flows through the channels toward the transducer and exits through the mouthpiece to the user, collecting the generated mist.

Next, the driver device 202 will be described first with reference to FIGS. 35 and 36. Air enters the mist generating device 201 through an air inlet port 207 that is in fluid communication with an airflow bridge within the driver device 202, as described below. Air flows along a flow path that changes the direction of the air flow by approximately 90 degrees to direct the air flow toward the ultrasound transducer 215 .

In some examples, the airflow arrangement is such that the airflow is substantially perpendicular to the atomization surface of the ultrasound transducer as it passes into the sonication chamber. configured to change the direction of air flow along the path.

The driver device 202 includes a driver device housing 246 that is at least partially made of metal. In some examples, driver device housing 246 is entirely aluminum (AL6063 T6) to protect internal components from the environment (dust, splash, etc.) and from damage from impact (such as accidental drops).

In some examples, the driver device housing 246 includes vents on its sides that allow ambient air to enter the device for two purposes: one to have ventilation around the electronic components; , keeping them within the operating temperature, these vents also act as air inlets through which air enters the device and then through the airflow bridge into the mist generating device 201.

Driver device housing 246 is elongated in shape with an interior chamber 247 that houses the components of driver device 202. One end of the driver device housing 246 is closed by an end cap 248. The other end of the driver device housing 247 has an opening 249 that provides an opening for the recess 203 of the driver device 202.

The driver device 202 consists of a battery 250 connected to a printed circuit board 251. In some examples, battery 250 is a 3.7V DC Li-Po battery with a capacity of 1140mAh and a discharge rate of 1OC. The high discharge rate is required due to the maximum 15V voltage amplification required by the ultrasonic transducer 215 for desired operation. The shape and size of the battery is designed according to the shape and size of the device and the space allocated for the power source, within physical constraints.

The printed circuit board 251 incorporates electronic components such as a processor and memory for realizing the electrical functions of the driver device 202. Charging pins 258 are provided at one end of printed circuit board 251 and extend through end cap 248 to provide a charging connection for charging battery 250.

A printed circuit board 251 is retained within the driver device housing 246 by a skeleton 252. Skeleton 252 has a channel 253 that receives printed circuit board 251. Skeleton 252 incorporates raised sides 254, 255 that support battery 250.

In some examples, skeleton 252 is manufactured using an industrial injection molding process. The molded plastic skeleton ensures that all parts are fixed and do not fit loosely inside the case. Further, when the mist generating device 201 is inserted into the driver device 202, a cover is formed to cover the front portion of a printed circuit board (PCB) that receives the mist generating device 201.

The driver device 202 is composed of an airflow sensor that functions as a switch for operating and supplying power to a transducer for generating ultrasonic waves or aerosol. The airflow sensor is mounted on a PCB within the device and requires a certain atmospheric pressure drop around it to activate the driver device 202. To this end, an airflow bridge 259 as shown in FIGS. 39 to 41 is designed with internal channels 260, 261 that direct air from the surroundings through the bridge 259 into the aerosol chamber 262. Scaffold 252 is comprised of opposing channels 256, 257 for receiving a portion of airflow bridge 259, as shown in FIG.

The internal channel of the airflow bridge 259 has a microchannel 263 (0.5 mm diameter) extending towards a chamber 264 that completely encloses the airflow sensor. When air enters through the side inlet and flows upward into the aerosol chamber 262, a negative pressure is created in the microchannel 263, triggering the airflow sensor to activate the device.

This device is a compact, portable, and advanced device that can accurately and safely monitor aerosolization. This is done by incorporating high quality electronic components designed with IPC class 3 (medical grade) in mind.

The electronic components of the driver device 202 are divided as follows:
1. Ultrasonicator The ultrasonicator generates ultrasonic waves at a high adaptive frequency (approximately 3 MHz) in order to obtain the most efficient aerosolization to date with particle sizes below 1 um for inhalation in mobile devices. Contact pads must be provided to receive the transducer 215 (piezoceramic disk (PZT)).

This section must not only provide high frequencies, but also always provide optimized cavitation while protecting the ultrasound transducer 215 from failure.

The mechanical deformation of the PZT is coupled to the alternating current voltage amplitude applied to it, and a maximum deformation must always be delivered to the PZT to ensure optimal functioning and delivery of the system during each ultrasound irradiation. There is.

However, to prevent PZT failure, it is necessary to accurately control the active power transferred to the PZT.

This is accomplished only by designing a custom, power management integrated circuit (PMIC) chip that does not exist on the market and is mounted on the printed circuit board of the driver device 202. This PMIC allows instantaneous modulation of the active power applied to the PZT without compromising the mechanical vibration amplitude of the PZT.

By performing PWM (Pulse Width Modulation) on the AC voltage applied to the PZT, the mechanical amplitude of vibration can be kept constant.

For this reason, the only "off-the-shelf" option was to use a digital-to-analog converter (DAC) to change the output AC voltage. Although the energy transferred to the PZT is reduced, mechanical deformation also occurs, which completely prevents proper aerosolization. In fact, as with voltage modulation, with effective duty cycle modulation the applied effective voltage will be the same, but the effective power delivered to the PZT will be degraded.In fact, it can be expressed as:

When considering the first harmonic, Irms is a function of the amplitude of the actual voltage applied to the transducer, and pulse width modulation changes the duration of the voltage applied to the transducer, thus controlling Irms.

The specific design of the PMIC employs a state-of-the-art design and enables ultra-precise control of the frequency range and steps applied to the PZT, including a complete set of feedback loops and monitoring paths used by the controller.

The remainder of the aerosolization section consists of a DC/DC boost converter and transformer that provides the necessary power to the PZT contact pads from a 3.7V battery.

Referring now to FIG. 43 of the accompanying drawings, driver device 202 is comprised of an ultrasound transducer driver microchip, referred to herein as a power management integrated circuit or PMIC 300. PMIC 300 is a microchip for driving a resonant circuit. The resonant circuit is an LC tank, an antenna, or in this case a piezoelectric transducer (ultrasonic transducer 215).

In this disclosure, the terms chip, microchip, and integrated circuit are used interchangeably. A microchip or integrated circuit is a single unit made up of multiple interconnected embedded components and subsystems. A microchip is, for example, at least partially made of a semiconductor such as silicon, and is manufactured using semiconductor manufacturing techniques.

Driver device 202 also includes a second microchip, referred to herein as a bridge integrated circuit or bridge IC 301, electrically connected to PMIC 300. Bridge IC 301 is a microchip for driving a resonant circuit such as an LC tank, antenna, or piezoelectric transducer. Bridge IC 301 is one unit composed of a plurality of interconnected built-in parts and subsystems.

In this example, the PMIC 300 and the bridge IC 301 are mounted on the same board of the driver device 202. In this example, the physical dimensions of the PMIC 300 are 1 to 3 mm wide and 1 to 3 mm long, and the physical dimensions of the bridge IC 301 are 1 to 3 mm wide and 1 to 3 mm long.

The mist generator 201 is configured to include a programmable integrated circuit or a one-time programmable integrated circuit or OTP IC 242 . When the mist generator 201 is coupled to the driver device 202 , the OTP IC is electrically connected to the PMIC 300 to receive power from the PMIC 300 so that the PMIC 300 can manage the voltage supplied to the OTP IC 242 . It has become. The OTP IC 242 is also connected to the communication bus 302 within the driver device 202 . In this example, communication bus 302 is an I2C bus, but in other examples, communication bus 302 is other types of digital serial communication buses.

The ultrasonic transducer 215 in the mist generating device 201 is electrically connected to the bridge IC 301, and the ultrasonic transducer 215 can be driven by an AC drive signal generated by the bridge IC 301 when the device 200 is used.

Driver device 202 comprises a processor in the form of a microcontroller 303 communicatively electrically coupled to communication bus 302 . In this example, microcontroller 303 is a Bluetooth ^™ low energy (BLE) microcontroller. Microcontroller 303 receives power from a low dropout regulator (LDO) 304 powered by battery 250. The LDO 304 provides a stable regulated voltage to the microcontroller 303 so that the microcontroller 303 can operate stably even when the voltage of the battery 250 varies.

The driver device 202 constitutes a voltage regulator in the form of a DC-DC boost converter 305 powered by a battery 250. Boost converter 305 increases the voltage of battery 250 to a programmable voltage VBOOST. Programmable voltage VBOOST is set by boost converter 305 in response to voltage control signal VCTL from PMIC 300. Although details will be described later, boost converter 305 outputs voltage VBOOST to bridge IC 301. In other examples, the voltage regulator is a step-down converter or other type of voltage regulator that outputs a selectable voltage.

Voltage control signal VCTL is generated by a digital-to-analog converter (DAC) implemented within PMIC 300 in this example. The DAC is not visible in FIG. 43 because it is integrated within the PMIC 300. The DAC and the technical advantages of integrating the DAC within the PMIC 300 are discussed in detail below.

In this example, the PMIC 300 is connected to a power connector in the form of a universal serial bus (USB) connector 306 such that the PMIC 300 can receive the charging voltage VCHRG when the USB connector 306 is coupled to a USB charger. .

In this example, the driver device 202 includes a first pressure sensor 307, which is a static pressure sensor. Further, the driver device 202 is configured to include a second pressure sensor 308, which is a dynamic pressure sensor in this example. However, in other examples, the driver device 202 is comprised of only one of the two pressure sensors 307, 308. As mentioned above, pressure sensors 307 , 308 sense changes in pressure within aerosol chamber 262 to sense when a user is inhaling mist inhaler 200 .

In this example, driver device 202 is comprised of a plurality of LEDs 308 controlled by PMIC 300.

Microcontroller 303 functions as a master device on communication bus 302, PMIC 300 is the first slave device, OTP IC 242 is the second slave device, second pressure sensor 308 is the third slave device, first pressure Sensor 307 becomes the first slave device. Communication bus 302 allows microcontroller 303 to control the following functions within driver device 202:

1. All functions of the PMIC are highly configurable by the microcontroller 303.
2. The current flowing through the ultrasound transducer 215 is sensed at a high common mode voltage (high side of the bridge) by a high bandwidth sense and rectifier circuit. The sensed current is converted to a voltage proportional to the effective current and provided as a buffered voltage to the current sense output terminal 309 of the bridge IC 301. This voltage is provided to the PMIC 300, sampled, and made available as a digital representation through an I2C request. Sensing the current flowing through the ultrasound transducer 215 forms part of the resonant frequency tracking function. As described herein, the device's ability to enable this functionality within bridge IC 301 provides significant technical advantages.
3. A DAC integrated within PMIC 300 (not shown in FIG. 43) allows the DC-DC boost converter voltage VBOOST to be programmed to be between 10V and 20V.
4. Microcontroller 303 enables the charger subsystem of device 202 to manage the charging of battery 250, which in this example is a single cell battery.
5. A light emitting diode (LED) driver module (not shown) is powered by the PMIC 300 to drive and digitally dim the LED 308 in either linear or gamma corrected mode.
6. Microcontroller 303 can read Pressure #1 and Pressure #2 sensor values from pressure sensors 307, 308.

Referring now to FIG. 44 of the accompanying drawings, PMIC 300 is, in this example, a self-contained chip or integrated circuit consisting of integrated subsystems and a plurality of pins that provide electrical input and output to PMIC 300. References in this disclosure to integrated circuits or chips are interchangeable, and both terms encompass semiconductor devices, which may be, for example, silicon.

The PMIC 300 includes an analog core 310 made up of analog components including a reference block (BG) 311, an LDO 312, a current sensor 313, a temperature sensor 314, and an oscillator 315.

Oscillator 315 is coupled to a delay locked loop (DLL) that outputs pulse width modulation (PWM) phase A and phase B, and oscillator 315 and DLL are coupled to H Generates a two-phase center-matched PWM output that drives the bridge.

The DLL consists of a plurality of delay lines connected end to end, and the total delay time of the delay lines is equal to the period of the main clock signal clk_m. In this example, the DLL is implemented in a digital processor subsystem, herein referred to as digital core 316, of PMIC 300, which receives a clock signal from oscillator 315 and a regulated power supply voltage from LDO 312. The DLL is implemented with a large number (eg, on the order of millions) of delay gates connected end-to-end in the digital core 316.

Implementing the oscillator 315 and DLL on the same integrated circuit of the PMIC300 to generate a two-phase center-aligned PWM signal is unique, as currently no signal generator component in the integrated circuit market constitutes this implementation. That's true.

As described herein, PWM allows the driver device 202 to adjust the resonant frequency of the ultrasonic transducer 215 to maintain an efficient transfer of electrical energy to kinetic energy to optimize mist generation. It is part of the functionality that allows accurate tracking.

In this example, PMIC 300 is configured to include a charger circuit 317 that controls charging of battery 250 with power from, for example, a USB power source.

PMIC 300 is configured to include an integrated power switch VSYS that configures PMIC 300 to power analog core 310 by power from battery 250 or by power from an external power source when battery 250 is charging. Ru.

PMIC 300 constitutes an embedded analog-to-digital converter (ADC) subsystem 318. The implementation of the ADC 318 along with the oscillator 315 within the same integrated circuit is unique in itself as there is no other integrated circuit in the integrated circuit market that consists of an oscillator and an ADC implemented as sub-blocks within an integrated circuit. . In conventional devices, the ADC is provided as a discrete component separate from the oscillator, and the ADC and oscillator are typically mounted on the same PCB. The problem with this conventional arrangement is that the two separate components, the ADC and the oscillator, take up unnecessary space on the PCB. Furthermore, conventional ADCs and oscillators are usually connected to each other by a serial data communication bus such as an I2C bus, and there is a problem in that the communication speed is limited to 400 kHz at maximum. In contrast to conventional devices, the PMIC 300 is configured with the ADC 318 and the oscillator 315 integrated within the same integrated circuit, so there is no lag in communication between the ADC 318 and the oscillator 315; 315 means that they can communicate with each other at high speed, for example, at the speed of the oscillator 315 (for example, from 3 MHz to 5 MHz).

In the PMIC 300 of this example, the oscillator 315 is operating at 5 MHz and generates a 5 MHz clock signal SYS CLOCK. However, in other examples, oscillator 315 generates a clock signal at a much higher frequency, up to 105 MHz. The integrated circuits described herein are all configured to operate at the high frequency of oscillator 315.

ADC 318 consists of multiple feedback input terminals or analog inputs 319 that constitute multiple GPIO inputs (IF_GPIO1-3). At least one of the feedback input terminals or analog inputs 319 receives a feedback signal from the H-bridge circuit within the bridge IC 301, the feedback signal being a parameter of the operation of the H-bridge circuit or the ultrasonic waveform of the H-bridge circuit with an AC drive signal. It shows parameters of an AC drive signal when driving a resonant circuit such as the transducer 215. As discussed below, the GPIO input is used to receive a current sense signal from bridge IC 301 that is indicative of the root mean square (rms) current reported by bridge IC 301. In this example, one of the GPIO inputs is a feedback input terminal that receives the feedback signal from the H-bridge within bridge IC 301.

ADC subsystem 318 samples analog signals received at multiple ADC input terminals 319 at a sampling frequency that is proportional to the frequency of the main clock signal. ADC subsystem 318 then uses the sampled analog signal to generate an ADC digital signal.

In this example, the ADC 318 contained in the PMIC 300 determines not only the RMS current flowing through the H-bridge 334 and the ultrasonic transducer 215, but also the voltages available in the system (e.g., VBAT, VCHRG, VBOOST), the temperature of the PMIC 300, and the voltage of the battery 250. It also samples temperature and GPIO inputs (IF_GPIO1-3) to enable future expansion.

Digital core 316 receives ADC-generated digital signals from the ADC subsystem and processes the ADC digital signals to generate driver control signals. Digital core 316 communicates driver control signals to a PWM signal generator subsystem (DLL 332) to control the PWM signal generator subsystem.

Rectifier circuits currently on the market have very limited bandwidth (typically less than 1 MHz). Since the oscillator 315 of the PMIC 300 operates at a maximum of 5 MHz or a maximum of 105 MHz, a high bandwidth rectifier circuit is implemented in the PMIC 300. As discussed below, sensing the RMS current in the H-bridge of bridge IC 301 forms part of a feedback loop that allows driver device 202 to drive ultrasound transducer 215 with high precision. The feedback loop is a game changer in the industry of driving ultrasonic transducers because it accommodates any process variations (variations in the resonant frequency) in piezoelectric transducer manufacturing and compensates for temperature effects on the resonant frequency. This is accomplished in part by the inventive implementation of integrating ADC 318, oscillator 315 and DLL within the same integrated circuit of PMIC 300. This integration allows these subsystems to communicate with each other at high speeds (eg, at clock frequencies of 5 MHz or up to 105 MHz). Reducing the lag between these subsystems is a game changer in the ultrasound industry, particularly in the field of mist generators.

The ADC 318 includes a battery voltage monitoring input VBAT, a charger input voltage monitoring input VCHG, voltage monitoring inputs VMON, VRTH, and a temperature monitoring input TEMP.

Temperature monitoring input TEMP receives a temperature signal from temperature sensor 314 built into PMIC 300 . This allows the PMIC 300 to accurately sense the actual temperature within the PMIC 300 and detect malfunctions within the PMIC 300 as well as malfunctions to other components on the printed circuit board that affect the temperature of the PMIC 300. In order to maintain the safety of the mist inhaler 200, the PMIC 300 can control the bridge IC 301 so as not to excite the ultrasonic transducer 215 if there is a malfunction.

Additional temperature sensor input VRTH receives a temperature sensing signal from an external temperature sensor within driver device 202 that monitors the temperature of battery 250. Accordingly, the PMIC 300 reacts to stop charging the battery 250 or otherwise shut down the driver device 202 in case of high battery temperature to reduce the risk of damage caused by excessively high battery temperatures. Is possible.

PMIC 300 is comprised in this example of an LED driver 320 that receives digital drive signals from digital core 316 and provides LED drive output signals to six LEDs 321-326 configured to be coupled to output pins of PMIC 300. Ru. Thus, LED driver 320 can drive and dim LEDs 321-326 in up to six independent channels.

The PMIC 300 includes a first digital-to-analog converter (DAC) 327 that converts a digital signal within the PMIC 300 into an analog voltage control signal and outputs it from the PMIC 300 via an output terminal VDAC0. The first DAC 327 converts the digital control signal generated by the digital core 316 into an analog voltage control signal, outputs it via the output terminal VDAC0, and controls a voltage regulator circuit such as the boost converter 305. In this manner, the voltage control signal is set at a predetermined level for modulation by an H-bridge circuit for driving a resonant circuit, such as the ultrasonic transducer 215, in response to a feedback signal indicative of the operation of the resonant circuit (ultrasonic transducer 215). A voltage regulator circuit is controlled to generate a voltage.

In this example, the PMIC 300 is configured to include a second DAC 328 that converts a digital signal within the PMIC 300 into an analog signal output from the PMIC 300 via the second analog output terminal VDAC1.

By embedding the DACs 327, 328 within the same microchip as the other subsystems of the PMIC 300, the DACs 327, 328 communicate quickly with the digital core 316 and other components within the PMIC 300 with no or minimal communication lag. I can do it. DACs 327, 328 provide analog outputs that control external feedback loops. For example, the first DAC 327 supplies a control signal VCTL to the boost converter 305 to control the operation of the boost converter 305. In other examples, DACs 327, 328 are configured to provide drive signals to a DC-DC buck converter instead of or in addition to boost converter 305. By integrating two independent DAC channels into the PMIC 300, the PMIC 300 can operate the feedback loop of any regulator used in the driver device 202, allowing the driver device 202 to control the ultrasound output power of the ultrasound transducer 215. It may be possible to adjust the ultrasonic transducer 215 and set analog thresholds for the absolute maximum current and temperature settings of the ultrasound transducer 215.

PMIC 300 constitutes a serial communication interface, in this example an I2C interface that includes an external I2C address set through a pin.

PMIC 300 is also comprised of various functional blocks including a digital machine (FSM) for implementing the functionality of the microchip. These blocks are explained in more detail below.

Referring now to FIG. 45 of the accompanying drawings, a pulse width modulation (PWM) signal generator subsystem 329 is incorporated within the PMIC 300. PWM generator system 329 is comprised of an oscillator 315, a frequency divider 330, a multiplexer 331, and a delay locked loop (DLL) 332. As will be described later, the PWM generation system 329 is a two-phase center alignment type PWM generator.

Frequency divider 330, multiplexer 331, and DLL 332 are implemented with digital logic components (eg, transistors, logic gates, etc.) within digital core 316.

In examples of this disclosure, the frequency range covered by oscillator 315 and each PWM generation system 329 is 50 kHz to 5 MHz or up to 105 MHz. The PWM generation system 329 has a frequency accuracy of ±1% and a spread over temperature of ±1%. In the current IC market, there is no IC with a built-in oscillator and two-phase center-matched PWM generator that can provide a frequency range of 50 kHz to 5 MHz or up to 105 MHz.

Oscillator 315 generates a main clock signal (clk_m) with a frequency of 50 kHz to 5 MHz, or up to 105 MHz. Main clock clk_m is input to frequency divider 330, which divides the frequency of main clock clk_m by one or more predetermined divisor amounts. In this example, the frequency divider 330 divides the frequency of the main clock clk_m by 2, 4, 8, and 16, and supplies the divided frequency clock to the multiplexer 331 as an output. The multiplexer 331 multiplexes the divided frequency clocks and supplies the divided frequency output to the DLL 332 . The signal passed to this DLL 332 is a frequency reference signal that controls the DLL 332 to output a signal at a desired frequency. Note that in other examples, the frequency divider 330 and the multiplexer 331 are omitted.

The oscillator 315 also generates two phases: a first phase clock signal Phase 1 and a second phase clock signal Phase 2. The phases of the first phase clock signal and the second phase clock signal are center aligned. As shown in Figure 46:
The first phase clock signal phase 1 goes high for a variable amount of time during the positive half period of clk_m and goes low during the negative half period of clk_m.
The second phase clock signal phase 2 goes high for a variable amount of time during the negative half period of clk_m and goes low during the positive half period of clk_m.

The signal is then sent to the DLL 332, which uses the first phase clock signal Phase 1 and the second phase clock signal Phase 2 to generate a double frequency clock signal. This double frequency clock signal has twice the frequency of the main clock signal clk_m. In this example, an "OR" gate within DLL 332 uses a first phase clock signal Phase 1 and a second phase clock signal Phase 2 to generate a double frequency clock signal. This doubled frequency clock or divided frequency coming from frequency divider 330 is selected based on the selected target frequency and is then used as a reference for DLL 332.

Within the DLL 332, a signal hereinafter referred to as "clock" represents the main clock clk_m doubled, and a signal hereinafter referred to as "clock_del" represents a replica of the clock delayed by one cycle. The clock and clock_del are passed through a phase frequency detector. Then, the node Vc is charged and discharged by the charge pump based on the polarity of the phase error. A control voltage is applied directly to control the delay of each and every delay unit within DLL 332 until the total delay of DLL 332 is exactly one period.

The DLL 332 controls the rising edges of the first phase clock signal Phase 1 and the second phase clock signal Phase 2 to be synchronized with the rising edge of the double frequency clock signal. DLL 332 adjusts the frequency and duty cycle of the first phase clock signal Phase 1 and the second phase clock signal Phase 2 in response to respective frequency reference signals and duty cycle control signals, and adjusts the frequency and duty cycle of the first phase clock signal Phase 1 and the second phase clock signal Phase 2, and adjusts the frequency and duty cycle of the first phase clock signal Phase 1 and the second phase clock signal Phase 2. A two-phase output signal Phase B is generated to drive the H-bridge or inverter to generate an AC drive signal to drive the ultrasound transducer.

The PMIC300 is composed of a first phase output signal terminal PHASE_A that outputs the first phase output signal phase A to the H bridge circuit, and a second phase output signal terminal PHASE_B that outputs the second phase output signal phase B to the H bridge circuit. has been done.

In this example, the DLL 332 adjusts the duty cycle of the first phase clock signal Phase 1 and the second phase clock signal Phase 2 by varying the delay time of each delay line of the DLL 332 in response to a duty cycle control signal. .

The clock is used at twice its frequency to ensure better accuracy. As shown in FIG. 47, if the frequency of the main clock clk_m is used for illustration purposes (which is not used in the examples of this disclosure), phase A is synchronized to the rising edge R of the clock, and phase B is synchronized to the falling edge R of the clock. Synchronize with edge F. The delay line of DLL 332 controls rising edges R, so for falling edges F, PWM generation system 329 will have to rely on perfect matching of the delay units of DLL 332, which may be imperfect. However, to eliminate this error, PWM generation system 329 uses a double frequency clock such that both Phase A and Phase B are synchronized with the rising edge R of the double frequency clock.

To perform a 20% to 50% duty cycle with a 2% step size, the delay line of DLL 332 consists of 25 delay units, with the output of each delay unit representing phase n. Ultimately, the phase of the output of the last delay unit will correspond to the input clock. Considering that all delays will be approximately the same, simple logic in digital core 316 will yield a specific duty cycle at the output of a specific delay unit.

Although the DLL 332 may not be able to lock on a period of delay, it is important to be careful with the activation of the DLL 332 as there may be more than one period, bringing the DLL 332 into a non-convergence zone. To avoid this problem, a start-up circuit is implemented in PWM generation system 329, which allows DLL 332 to start up from a known, deterministic state. The startup circuit also allows DLL 332 to start up with minimal delay.

In examples of the present disclosure, the frequency range covered by the PWM generator system 329 is expanded so that the delay unit within the DLL 332 provides a delay of 4 ns (for an oscillator frequency of 5 MHz) to 400 ns (for an oscillator frequency of 50 kHz). It is possible to provide To accommodate these different delays, a capacitor Cb is included in the PWM generation system 329, and the capacitor value is selected to provide the required delay.

Phase A and phase B are output from DLL 332 and passed to bridge IC 301 via digital IO, allowing phase A and phase B to be used to control the operation of bridge IC 301.

Next, the battery charging function of driver device 202 will be explained in more detail. The battery charging subsystem is comprised of a charger circuit 317 that is internal to PMIC 300 and controlled by a digital charge controller hosted on PMIC 300. Charger circuit 317 is controlled by microcontroller 303 via communication bus 302 . The battery charging subsystem is capable of charging a single cell lithium polymer (LiPo) or lithium ion (Li-ion) battery, such as battery 250 described above.

In this example, the battery charging subsystem is capable of charging the battery or batteries with up to 1 A of charging current from a 5V power source (eg, a USB power source). Via communication bus 302 (I2C interface), one or more of the following parameters can be programmed to adapt battery charging parameters.

The charging voltage can be set between 3.9V and 4.3V in 100mV steps.

The charging current can be set from 150mA to 1000mA in 50mA increments.

The precharge current is 1/10 of the charging current.

The precharge and quick charge timeouts can be set between 5 and 85 minutes and between 20 and 340 minutes, respectively.

Optionally, an external negative temperature coefficient (NTC) thermistor can be used to monitor battery temperature.

In some examples, the battery charging subsystem reports one or more of the following events by generating an interrupt to the host microcontroller 303.
Battery Detection Battery Charging Battery Fully Charged No Battery Charging Timeout Charging power source is below undervoltage limit

The main advantage of embedding charger circuit 317 in PMIC 300 is that all described programming options and event indications can be implemented within PMIC 300 ensuring safe operation of the battery charging subsystem. Furthermore, significant manufacturing cost and PCB space savings can be achieved compared to conventional mist inhalers consisting of discrete components of the charging system mounted separately on the PCB. The charger circuit 317 also allows for versatile settings of charging current and voltage, different fault timeouts, and multiple event flags for detailed condition analysis.

Next, the analog-to-digital converter (ADC) 318 will be explained in more detail. The inventors had to overcome significant technical challenges in order to integrate the ADC 318 into a PMIC 300 with a high speed oscillator 315. Furthermore, integrating ADC 318 within PMIC 300 goes against traditional approaches in the art that rely on using one of the many discrete ADC devices available on the IC market.

In this example, ADC 318 samples at least one parameter within an ultrasound transducer driver chip (PMIC 300) at a sampling rate equal to the frequency of main clock signal clk_m. In this example, ADC 318 is a 10-bit analog-to-digital converter that can unload digital sampling from microprocessor 303 to conserve microprocessor 303 resources. Integrating the ADC 318 within the PMIC 300 also avoids the need to use the I2C bus, which would otherwise slow down the sampling capabilities of the ADC (conventional devices typically (typically relies on the I2C bus to transfer data at limited clock speeds of up to 400 kHz).

In examples of this disclosure, one or more of the following parameters may be sequentially sampled by ADC 318:

i. The rms current signal received by the ultrasound transducer driver chip (PMIC300) from the external inverter circuit driving the ultrasound transducer. In this example, this parameter is the root mean square (rms) current reported by bridge IC 301. Sensing the effective current is important to implementing the feedback loop used to drive the ultrasound transducer 215. Since the ADC 318 does not rely on this information being transmitted over the I2C bus, it is able to sense the effective current directly from the bridge IC 301 via a signal with minimal or no delay. This provides significant speed and accuracy advantages compared to conventional devices that are limited by the relatively low speed of the I2C bus.
ii. Voltage of battery connected to PMIC300.
iii. Voltage of charger connected to PMIC300.
iv. A temperature signal indicating the chip temperature of PMIC300, etc. As mentioned above, since the temperature sensor 314 is built into the same IC as the oscillator 315, this temperature can be measured very accurately. For example, if the temperature of the PMIC 300 increases, the PMIC 300 controls the current, frequency, and PWM, which controls the oscillation of the transducer, which controls the temperature.
v. Two external terminals.
vi. External NTC temperature sensor to monitor battery pack temperature.

In some examples, ADC 318 sequentially samples one or more of the sources, eg, in a round-robin manner. ADC 318 samples the source at a high speed, such as the rate of oscillator 315, which may be up to 5 MHz or up to 105 MHz.

In some examples, device 202 is configured to allow the user or device manufacturer to specify how many samples to take from each source for averaging. For example, a user can configure the system to take 512 samples from the rms current input, 64 samples from the battery voltage, 64 samples from the charger input voltage, 32 samples from the external pins, and 8 samples from the NTC pin. Furthermore, the user can also specify whether to skip one of the above sources.

In some examples, a user may specify two digital thresholds for each source that divide the total range into multiple zones (eg, three zones). An interrupt can then be configured to occur when the sampled value changes from zone 2 to zone 3.

Conventional ICs currently available on the market cannot perform the above functions of PMIC 300. Sampling with such flexibility and granularity is most important when driving resonant circuits or components such as ultrasound transducers.

In this example, PMIC 300 is configured with an 8-bit general purpose digital input/output port (GPIO). Each port can be configured as a digital input and a digital output. Further, as shown in the table of FIG. 48, some ports have an analog input function.

GPIO7-GPIO5 ports of PMIC 300 can be used to address devices on communication (I2C) bus 302. Eight identical devices can then be used on the same I2C bus. This is a unique feature in the IC industry because eight identical devices can be used on the same I2C bus without address conflicts. This is achieved by each device reading the status of GPIO7-GPIO5 during the first 100 μs after the PMIC 300 is activated, and causing the PMIC 300 to internally store the address of that part. After the PMIC 300 powers up, the GPIO can be used for other purposes.

As described above, the PMIC 300 includes the 6-channel LED driver 320. In this example, the LED driver 320 is configured with a 5V N-Channel Metal-Oxide Semiconductor (NMOS) current source. The LED driver 320 is configured so that the LED current can be set at four discrete levels: 5 mA, 10 mA, 15 mA, and 20 mA. The LED driver 320 is configured to dim each LED channel with a 12-bit PWM signal, with or without gamma correction. The LED driver 320 is configured to vary the PWM frequency between 300Hz and 1.5KHz. This functionality is unique in the field of ultrasonic mist inhalers as it is incorporated as a subsystem of the PMIC300.

In this example, PMIC 300 is comprised of two independent 6-bit digital-to-analog converters (DACs) 327, 328 incorporated into PMIC 300. The purpose of the DACs 327, 328 is to output analog voltages to operate the feedback path of an external regulator (eg, DC-DC boost converter 305 buck converter or LDO). Additionally, in some examples, DACs 327, 328 may also be used to dynamically adjust the overcurrent shutdown level of bridge IC 301, as described below.

The output voltage of each DAC 327, 328 is programmable between 0V and 1.5V, or between 0V and V_battery (Vbat). In this example, control of the DAC's output voltage is done via I2C commands. The incorporation of two DACs into the PMIC300 is unique and allows for dynamic monitoring and control of current. If either DAC 327 or 328 is an external chip, it will be subject to the same speed limitations as the I2C protocol. When all these built-in functions are within the PMIC, the active power monitoring arrangement of device 202 functions at optimal efficiency. If these were external components, the active power monitoring arrangement would be completely inefficient.

Referring now to FIG. 49 of the accompanying drawings, bridge IC 301 is a microchip that constitutes an embedded power switching circuit 333. In this example, power switching circuit 333 is an H-bridge 334 shown in FIG. 50, which is described in detail below. However, the bridge IC 301 of other examples may incorporate a power switching circuit in place of the H bridge 334 as long as it performs an equivalent function of generating an AC drive signal for driving the ultrasonic transducer 215. Good things will be understood.

Bridge IC 301 constitutes a first phase terminal phase A that receives a first phase output signal phase A from the PWM signal generation subsystem of PMIC 300 . Bridge IC 301 also configures a second phase terminal Phase B that receives a second phase output signal Phase B from the PWM signal generator subsystem of PMIC 300 .

Bridge IC 301 is comprised of a current sensing circuit 335 that directly senses the current flow in H-bridge 334 and provides an RMS current output signal through the RMS_CURR terminal of bridge IC 301. The current detection circuit 335 is configured for overcurrent monitoring to detect that the current flowing through the H bridge 334 is equal to or higher than a predetermined threshold. Integrating all of the power switching circuit 333 and current detection circuit 335 that make up the H-bridge 334 into the same built-in circuit of the bridge IC 301 is a unique combination in the IC market. At present, there is no other integrated circuit in the IC market that constitutes an H-bridge in which a circuit for detecting the effective value current flowing through the H-bridge is embedded.

Bridge IC 301 is comprised of a temperature sensor 336 that includes overtemperature monitoring. The temperature sensor 336 is configured to shut down the bridge IC 301 or disable at least a portion of the bridge IC 336 if the temperature sensor 336 detects that the bridge IC 301 is operating at a temperature above a predetermined threshold. configured. Accordingly, temperature sensor 336 provides an integrated safety feature that prevents damage to bridge IC 301 or other components within driver device 202 if bridge IC 301 operates at excessively high temperatures.

The bridge IC 301 includes a digital state machine 337 integrally connected to a power switching circuit 333. Digital state machine 337 receives phase A and phase B signals from PMIC 300 and, for example, an ENABLE signal from microcontroller 303. Digital state machine 337 generates a timing signal based on first phase output signal phase A and second phase output signal phase B.

The digital state machine 337 generates timing signals corresponding to the phase A signal and the phase B signal as well as the BRIDGE signal to control the power switching circuit 333. PR signal and BRIDGE The EN signal is output to the power switching circuit 333. As a result, the digital state machine 337 outputs a timing signal to switches T ₁ -T ₄ of the H-bridge circuit 334, and the H-bridge circuit outputs an AC drive signal for driving a resonant circuit such as the ultrasonic transducer 215. The switches T ₁ to T ₄ are controlled to turn on and off in sequence so that

The details will be described later, but in order to dissipate the energy stored in the resonant circuit (ultrasonic transducer 215), the switching sequence turns off the first switch _T1 and the second switch _T2 , and turns off the third switch _T3 and the second switch T2. It consists of a free float period in which four switches _T4 are turned on.

Bridge IC 301 is configured to include a test controller 338 that can test bridge IC 301 to determine whether embedded components within bridge IC 301 are operating properly. The test controller 338 DATA, TEST CLK, TEST It is coupled to the LOAD terminal so that it can be connected to an external control device that sends data to the bridge IC 301 and tests the operation of the bridge IC 301. In addition, the bridge IC301 is TST It constitutes a TEST BUS that can test the digital communication bus within the bridge IC 301 via the PAD terminal.

The bridge IC 301 is configured to include a power-on reset circuit (POR) 339 that controls the startup operation of the bridge IC 301. The POR 339 allows the bridge IC 301 to start up normally only when the power supply voltage is within a predetermined range. If the power supply voltage is outside the predetermined range, for example if the power supply voltage is too high, the POR 339 delays activation of the bridge IC 301 until the power supply voltage is within the predetermined range.

Bridge IC 301 is configured to include a reference block (BG) 340 that provides accurate reference voltages for use by other subsystems of bridge IC 301.

Bridge IC 301 constitutes a current reference 341 that provides accurate current to power switching circuitry 333 and/or other subsystems within bridge IC 301 such as current sensor 335.

Temperature sensor 336 continuously monitors the temperature of the silicon of bridge IC 301. If the temperature exceeds a predetermined temperature threshold, the power switching circuit 333 is automatically switched off. Additionally, overheating may be reported to an external host to notify the external host that an overheating event has occurred.

Digital state machine (FSM) 337 generates timing signals for power switching circuit 333, in this example, for controlling H-bridge 334.

Bridge IC 301 is comprised of comparators 342, 343 that compare signals from various subsystems of bridge IC 301 to voltage and current references 340, 341 and provide reference output signals via pins of bridge IC 301.

Referring again to FIG. 50 of the accompanying drawings, the H-bridge 334 in this example is comprised of four switches in the form of NMOS field effect transistor (FET) switches on either side of the H-bridge 334. H-bridge 334 consists of four switches or transistors T ₁ -T ₄ connected in an H-bridge configuration, each transistor T ₁ -T ₄ being driven by a respective logic input AD. Transistors T ₁ -T ₄ are configured to be driven by an internally generated bootstrap voltage using two external capacitors Cb connected as shown in FIG.

The H bridge 334 configures input/output of various power supplies connected to each pin of the bridge IC 301. H-bridge 334 receives programmable voltage VBOOST output from boost converter 305 via a first power supply terminal labeled VBOOST in FIG. H-bridge 334 constitutes a second power supply terminal labeled VSS_P in FIG.

H-bridge 334 configures outputs OUTP, OUTN configured to connect to respective terminals of ultrasound transducer 215 such that the AC drive signal output from H-bridge 334 can drive ultrasound transducer 215.

The switching of the four switches or transistors T ₁ -T ₄ is controlled by switching signals from the digital state machine 337 via logic inputs AD. Although FIG. 50 shows four transistors T ₁ -T ₄ , in other examples, H-bridge 334 incorporates more transistors or other switching components to achieve the functionality of an H-bridge. I hope you understand that.

In this example, H-bridge 334 operates with switching power between 22W and 50W to provide an AC drive signal with sufficient power to drive ultrasound transducer 215 to optimally generate mist. The voltage at which H-bridge 334 switches in this example is ±15V, but in other examples it is ±20V.

In this example, H-bridge 334 switches at a frequency of 3 MHz to 5 MHz, or up to 105 MHz. This is a high switching speed compared to conventional integrated circuit H-bridges available on the IC market. For example, conventional integrated circuit H-bridges currently available on the IC market are configured to operate at a maximum frequency of only 2 MHz. Apart from the bridge IC 301 described herein, no conventional integrated circuit H-bridge available on the IC market is capable of operating from 22V to 50V power at frequencies up to 5MHz, let alone up to 105MHz.

Next, referring to FIG. 51 of the accompanying drawings, the current sensor 335, as shown in FIG.
It consists of positive and negative current sensing resistors RshuntP, RshuntN connected in series with the respective high and low sides of H-bridge 334. The current sensing resistors RshuntP, RshuntN are 0.1 Ω. It is a low value resistance. Current sensor 335 includes a first voltage sensor in the form of a first operational amplifier 344 that measures the voltage drop across the first current sensor resistor RshuntP, and a second voltage sensor that measures the voltage drop across the second current sensor resistor RshuntN. a second voltage sensor in the form of an operational amplifier 345. In this example, the gain of each operational amplifier 344, 345 is 2V/V. The output of each operational amplifier 344, 345 is 1 mA/V in this example. Current sensor 335 consists of a pull-down resistor R _cs , which in this example is 2 kΩ. The outputs of the operational amplifiers 344, 345 provide an output CSout that has been passed through a low pass filter 346 that removes transients in the signal CSout. The output Vout of the low-pass filter 346 is the output signal of the current sensor 335.

In this manner, current sensor 335 measures alternating current flowing through H-bridge 334 and through ultrasound transducer 215, respectively. Current sensor 335 converts the alternating current to an equivalent RMS output voltage (Vout) with respect to ground. Current sensor 335 has high bandwidth capability because H-bridge 334 can operate at frequencies up to 5 MHz or in some examples up to 105 MHz. The output of current sensor 335, Vout, reports a positive voltage corresponding to the measured AC effective current flowing through ultrasound transducer 215. In this example, the output voltage Vout of the current sensor 335 is fed back to the control circuit within the bridge IC 301, and when the current flowing through the H bridge 334 and, by extension, the current flowing through the transducer 215 exceeds a predetermined threshold, the bridge IC 301 becomes H. Allows bridge 334 to be stopped. Furthermore, an overcurrent threshold event occurs when the bridge IC 301 The overcurrent event is reported to the first comparator 342 of the bridge IC 301 so that it can be reported via the TRIGG pin.

Next, with reference to FIG. 52 of the accompanying drawings, control of the H-bridge 334 will be described with reference to an equivalent piezoelectric model of the ultrasonic transducer 215.

Switching of transistors T ₁ -T ₄ through inputs AD to generate a positive voltage across the outputs OUTP, OUTN of the H-bridge 334 (note the direction of the arrows), as indicated by V_out in FIG. The sequence is:
1. Positive output voltage across ultrasound transducer 215: A-on, B-off, C-off, D-on 2. Transition from positive output voltage to zero: A-off, B-off, C-off, D-on. During this transition, if there is a switching error or delay in A, C is switched off first to minimize or avoid power loss by minimizing or avoiding current flowing through A and C.
3. Output voltage zero: A-OFF, B-OFF, C-ON, D-ON. In this phase of zero output voltage, the output terminals OUTP and OUTN of the H bridge 334 are grounded by the C and D switches that remain on. This dissipates the energy stored in the capacitor of the equivalent circuit of the ultrasonic transducer and minimizes the voltage overshoot of the switching waveform voltage applied to the ultrasonic transducer.
4. Transition from zero to negative output voltage A-OFF, B-OFF, C-ON, D-OFF.
5. Negative output voltages across ultrasound transducer 215: A-OFF, B-ON, C-ON, D-OFF.

It will be appreciated that at high frequencies, up to 5 MHz, or even up to 105 MHz, the duration of each part of the switching sequence is very short, on the order of nanoseconds or picoseconds. For example, if the switching frequency is 6 MHz, each portion of the switching sequence occurs in approximately 80 nanoseconds.

A graph showing the output voltages OUTP and OUTN of the H-bridge 334 according to the above switching sequence is shown in FIG. 53 of the accompanying drawings. A zero output voltage portion of the switching sequence is included to accommodate energy stored by the ultrasound transducer 215 (eg, energy stored by a capacitor in the ultrasound transducer's equivalent circuit). This minimizes voltage overshoot of the switching waveform voltage applied to the ultrasonic transducer, as described above, thereby minimizing unnecessary power dissipation and heating in the ultrasonic transducer. .

Further, by minimizing or eliminating voltage overshoot, it is possible to prevent the transistors in the bridge IC 301 from receiving a voltage exceeding the rated voltage, thereby reducing the risk of damage to the transistors. Additionally, minimizing or eliminating voltage overshoot allows bridge IC 301 to accurately drive ultrasound transducers in a manner that minimizes disruption of the current sensing feedback loops described herein. As a result, the bridge IC 301 can drive the ultrasonic transducer at a high frequency of up to 5 MHz or up to 105 MHz and with a power as high as 22 W to 50 W or 70 W.

Bridge IC 301 in this example is controlled by PMIC 300 and is configured to operate in two different modes, referred to herein as forced mode and native frequency mode. These two modes of operation are newer than existing bridge ICs. In particular, native frequency mode is a major innovation that offers substantial advantages in the accuracy and efficiency of driving ultrasound transducers compared to conventional devices.

Forced frequency mode (FFM)
In forced frequency mode, the H-bridge 334 is controlled in the order described above, but at a user-selectable frequency. As a result, H-bridge transistors T ₁ -T ₄ are forced to control and switch the output voltage across ultrasound transducer 215 independently of the natural resonant frequency of ultrasound transducer 215. Therefore, in forced frequency mode, the H-bridge 334 can drive the ultrasound transducer 215 with a resonant frequency f1 at a different frequency f2.

Driving an ultrasound transducer at a frequency different from its resonant frequency may be appropriate to adapt its operation to different applications. For example, it may be appropriate to drive the ultrasound transducer at a frequency slightly offset from the resonant frequency (for mechanical reasons to prevent mechanical damage to the transducer). Alternatively, it may be appropriate to drive the ultrasound transducer at a lower frequency, but the ultrasound transducer has a different natural resonant frequency due to its size.

Driver device 202 controls bridge IC 301 to drive ultrasound transducer 215 in a forced frequency mode, responsive to the particular application or configuration of driver device 202 for a particular ultrasound transducer. For example, the driver device 202 operates in a forced frequency mode when the mist inhaler 200 is used for a particular application, such as generating a mist from a liquid of a particular viscosity containing a drug for delivery to a user. It may be configured to do so.

Native frequency mode (NFM)
The following native frequency mode of operation is an important development, offering advantages in improved accuracy and efficiency compared to conventional ultrasonic drivers currently available on the IC market.

Native frequency mode operation follows the same switching sequence as described above, but the timing of the zero output portion of the sequence is adjusted to minimize or avoid problems that can occur due to current spikes in forced frequency mode operation. . These current spikes occur when the voltage across ultrasound transducer 215 switches to its opposite voltage polarity. Ultrasonic transducers made of piezoelectric crystals have an electrical equivalent circuit that incorporates capacitors connected in parallel (see, for example, the piezo model in Figure 52). If the voltage across the ultrasound transducer is hard switched from a positive voltage to a negative voltage, due to the high dV/dt, there can be a large current flow as the energy stored in the capacitor is dissipated.

Native frequency mode avoids hard switching the voltage across ultrasound transducer 215 from a positive voltage to a negative voltage (and vice versa). Instead, prior to applying the inversion voltage, the ultrasound transducer 215 (piezoelectric crystal) is allowed to free float with zero voltage applied across its terminals for a free float period. The PMIC 300 connects the bridge IC 301 so that the current flowing inside the ultrasound transducer 215 (due to the energy stored in the piezoelectric crystal) during the free float period reverses the voltage across the terminals of the ultrasound transducer 215. Set the drive frequency.

As a result, when the H-bridge 334 applies a negative voltage to the terminals of the ultrasonic transducer 215, the ultrasonic transducer 215 (the capacitor in the equivalent circuit) is already reverse charged and there is no high dV/dt, resulting in a current spike. does not occur.

However, it should be appreciated that when the ultrasound transducer 215 is first activated, it takes time for the charge within the ultrasound transducer 215 (piezoelectric crystal) to build up. Therefore, the ideal situation in which the energy within the ultrasound transducer 215 reverses voltage during the free float period occurs only after the oscillations within the ultrasound transducer 215 have accumulated charge. To accommodate this, when the bridge IC 301 activates the ultrasound transducer 215 for the first time, the PMIC 300 reduces the power supplied to the ultrasound transducer 215 via the H-bridge 334 to a first value that is a low value (e.g. 5V). PMIC 300 then increases the power supplied to ultrasound transducer 215 via H-bridge 334 to a second value higher than the first value for a period of time to build up the energy stored within ultrasound transducer 215. (for example, 15V). Current spikes also occur during this ramp of oscillation until the current within the ultrasound transducer 215 is sufficiently developed. However, by using a low first voltage during startup, those current spikes can be kept low enough to minimize their impact on the operation of the ultrasound transducer 215.

In order to realize the native frequency mode, the driver device 202 controls the frequency of the oscillator 315 and the duty cycle (ratio of turn-on time to free float time) of the AC drive signal output from the H-bridge 334 with high precision. In this example, the driver device 202 includes three control loops for adjusting the oscillator frequency and duty cycle to make the voltage reversal at the terminals of the ultrasound transducer 215 as accurate as possible and to minimize or avoid current spikes. Execute. Precise control of the oscillator and duty cycle using a control loop is an important advance in the field of IC ultrasonic drivers.

During native frequency mode operation, current sensor 335 senses the current flowing through ultrasound transducer 215 (resonant circuit) during the free float period. The digital state machine 337 switches either the first switch T ₁ or the second switch T ₂ when the current sensor 335 senses that the current flowing through the ultrasound transducer 215 (resonant circuit) is zero during the free float period. Adapt the timing signal to turn on.

FIG. 54 of the accompanying drawings shows the oscillator voltage waveform 347 (V(osc)), the switching waveform 348 due to the turn-on and turn-off of the left high switch T ₁ of the H-bridge 334, and the turn-on and turn-off of the right high switch T ₂ of the H-bridge 334. A switching waveform 349 due to turn-off is shown. During the free-float period 350, the high switches of H-bridge 334, T ₁ and T ₂ , are both turned off (free-float phase). The duration of the free float period 350 is controlled by the magnitude of the free float control voltage 351 (Vphioff).

FIG. 55 of the accompanying drawings shows the voltage waveform 352 at the first terminal of the ultrasonic transducer 215 (the voltage waveform is inverted at the second terminal of the ultrasonic transducer 215) and the piezoelectric current 353 flowing through the ultrasonic transducer 215. It shows. The piezo current 353 represents a (nearly) ideal sinusoidal waveform (this is never possible in forced frequency mode or in any bridge on the IC market).

Before the sine wave of the piezo current 353 reaches zero, the high switch T ₁ on the left side of the H-bridge 334 is turned off (here, the switch T ₁ is turned off when the piezo current 353 is about 6 A). The remaining piezoelectric current 353 flowing through the ultrasonic transducer 215 due to the energy stored in the ultrasonic transducer 215 (piezo equivalent circuit capacitor) serves as voltage reversal during the free float period 350. The piezo current 353 decays to zero during the free float period 350, after which it transitions into a negative current flow regime. The terminal voltage of the ultrasonic transducer 215 decreases from the power supply voltage (19V in this case) to 2V or less, and stops decreasing when the piezoelectric current 353 becomes zero. This is the optimal time to turn on the low side switch T ₃ of H-bridge 334 to minimize or avoid current spikes.

Compared to the forced frequency mode described above, the native frequency mode has at least three advantages.
1. Current spikes associated with hard switching of package capacitors are significantly reduced or completely avoided.
2. There is almost no power loss due to hard switching.
3. Frequency control is performed by a control loop and can be brought close to the resonant frequency of the piezoelectric transducer (the natural resonant frequency of the piezoelectric transducer).

For frequency regulation by control loop (advantage 3 above), PMIC 300 starts by controlling bridge IC 301 to drive ultrasound transducer 215 at a frequency above the resonance of the piezoelectric transducer. Thereafter, the PMIC 300 controls the bridge IC 301 so that the frequency of the AC drive signal is attenuated/reduced during startup. When the frequency approaches the resonant frequency of the piezoelectric transducer, the piezoelectric current develops/increases rapidly. Once the piezo current is high enough to cause the desired voltage reversal, the frequency attenuation/reduction is stopped by the PMIC 300. The PMIC 300 control loop then takes over adjusting the frequency and duty cycle of the AC drive signal.

In forced frequency mode, the power supplied to the ultrasound transducer 215 is controlled through duty cycle and/or frequency shifting and/or by varying the supply voltage. However, in this example, in native frequency mode, the power supplied to ultrasound transducer 215 is controlled only through the supply voltage.

In this example, in the setup phase of the operation of the driver device, the bridge IC 301 is configured such that the first switch T ₁ and the second switch T 2 are turned off, and the third switch T ₃ and the fourth switch T ₄ are turned on _. is configured to measure the length of time until the current flowing through the ultrasonic transducer 215 (resonant circuit) becomes zero when Then, the bridge IC 301 sets the length of the free float period to be equal to the measured length of time.

Referring now to FIG. 56 of the accompanying drawings, PMIC 300 and bridge IC 301 in this example are designed to operate together as a companion chipset. PMIC 300 and bridge IC 301 are electrically connected to communicate with each other. PMIC 300 and bridge IC 301 are electrically connected to communicate with each other. In this example, there is an interconnect between PMIC 300 and bridge IC 301 that enables two categories of communication:

1. Control signal 2. Feedback Signal The connection between the PHASE_A terminal and PHASE_B terminal of the PMIC 300 and the bridge IC 301 is for transmitting a PWM modulated control signal that drives the H bridge 334. The connection between the EN_BR terminal of the PMIC 300 and the bridge IC 301 transmits an EN_BR control signal that triggers activation of the H bridge 334. The timing between the PHASE_A, PHASE_B, EN_BR control signals is important and is handled by the PMIC 300's digital bridge control.

Connections between the CS, OC, and OT terminals of the PMIC 300 and the bridge IC 301 return CS (current sensing), OC (overcurrent), and OT (overtemperature) feedback signals from the bridge IC 301 to the PMIC 300. Most notably, the CS (current sense) feedback signal consists of a voltage corresponding to the rms current flowing through the ultrasound transducer 215 as measured by the current sensor 335 of the bridge IC 301.

The OC (over current) and OT (over temperature) feedback signals are digital signals that indicate that either an over current or over voltage event has been detected by bridge IC 301. In this example, overcurrent and overtemperature thresholds are set with external resistors. Alternatively, it is also possible to dynamically set the threshold in response to a signal passed from one of the two DAC channels VDAC0, VDAC1 from the PMIC 300 to the OC_REF terminal of the bridge IC 301.

In this example, the design of PMIC 300 and bridge IC 301 allows the pins of these two integrated circuits to be connected directly to each other (e.g., via copper tracks on the PCB), thus allowing the communication of signals between PMIC 300 and bridge IC 301. It is possible to ensure that only minimal delays occur. This provides a significant speed advantage compared to conventional bridges in the IC market, which are typically controlled by signals over a digital communication bus. For example, a standard I2C bus is clocked at only 400 kHz, which is too slow to communicate sampled data at the high clock speeds of up to 5 MHz of the examples of this disclosure.

Although examples of the present disclosure have been described in connection with microchip hardware, other examples of the present disclosure operate on the components and subsystems of each microchip to perform the functions described herein. It will be understood that it consists of a method. For example, the PMIC 300 and bridge IC 301 may be operated in either forced frequency mode or native frequency mode.

Referring now to FIG. 57 of the accompanying drawings, the OTP IC 242 includes a power-on reset circuit (POR) 354, a bandgap reference (BG) 355, a capless low dropout regulator (LDO) 356, and a communication (e.g., I2C) interface. 357, a one-time programmable memory bank (eFuse) 358, an oscillator 359, and a general purpose input/output interface 360. The OTP IC 242 also includes a digital core 361 including a cryptographic authenticator. In this example, the cryptographic authenticator uses ECDSA (Elliptic Curve Digital Signature Algorithm) to encrypt/decrypt data stored in the OTP IC 242 and data transmitted to and received from the OTP IC 242.

The POR 354 ensures that the OTP IC 242 starts up normally only when the power supply voltage is within a predetermined range. If the power supply voltage is outside the predetermined range, the POR 354 resets the OTP IC 242 and waits until the power supply voltage is within the predetermined range.

BG 355 provides accurate reference voltage and current to LDO 356 and oscillator 359. LDO 356 supplies digital core 361, communication interface 357, and eFuse memory bank 358.

OTP IC 242 is configured to operate in at least the following modes:
Fuse Programming: During fuse programming (programming of one-time programmable memory), high current is required to burn the associated fuses in the eFuse memory bank 358. In this mode, a higher bias current is provided to maintain the gain and bandwidth of the regulation loop.

Read Fuse: In this mode, a moderate current is required to maintain a read fuse within the eFuse memory bank 358. This mode is executed upon power-up of the OTP IC 242 and transfers the contents of the fuse to the shadow register. In this mode, the regulation loop gain and bandwidth are set to lower values than in fuse mode.

Normal operation: In this mode, the LDO 356 is driven with a very low bias current, allowing the OTP IC 242 to operate at low power, thereby minimizing the power consumption of the OTP IC 242.

The oscillator 359 supplies necessary clocks to the digital core/engine 361 during a test (SCAN test), during fixing, and during normal operation. Oscillator 359 is trimmed to accommodate tight timing requirements during fusing mode.

In this example, the communication interface 357 complies with the FM+ specification of the I2C standard, but also complies with slow mode and fast mode. The OTP IC 242 uses the communication interface 357 to communicate with the driver device 202 (host) for exchanging data and keys.

Digital core 361 implements the control and communication functions of OTP IC 242. The cryptographic authenticator of the digital core 361 determines that the OTP IC 242 performs self-authentication with the driver device 202 (for example, using an ECDSA encrypted message), that the OTP IC 242 is genuine, and that the OTP IC 242 is the driver device. 202 (or other products).

Referring to FIG. 58 of the accompanying drawings, OTP IC 242 performs the following PKI procedures to authenticate OTP IC 242 for use with a host (e.g., driver device 202):
1. Verification of signer public key: The host requests the manufacturer public key and certificate. The host verifies the certificate with the certificate authority's public key.
2. Verification of device public key: If verification is successful, the host requests the device public key and certificate. The host verifies the certificate using the manufacturing public key.
3. Challenge-Response: If the verification is successful, the host creates a random number challenge and sends it to the device. The final product signs the random number challenge with the device's private key.
4. The signature is sent back to the host for verification using the device's public key.

If all steps of the authentication procedure are successfully completed, the chain of trust has been verified to the root of trust, and the OTP IC 242 has been successfully authenticated for use with the host. However, if any step of the authentication procedure fails, the OTP IC 242 is not authenticated for use with the host and use of the device incorporating the OTP IC 242 is restricted or prevented.

The driver device is configured with an AC driver that converts voltage from the battery into an AC drive signal of a predetermined frequency to drive the ultrasonic transducer.

The driver device constitutes a real power monitoring arrangement for monitoring the real power used by the ultrasonic transducer (described above) when the ultrasonic transducer is driven by an alternating current drive signal. The active power monitoring arrangement provides a monitoring signal indicative of the active power used by the ultrasound transducer.

A processor within the driver device controls the AC driver and receives supervisory signal drive from the active power monitoring arrangement.

The memory of the driver device stores instructions that, when executed by the processor, cause the processor to:
A. Controlling the AC driver to output an AC drive signal to the ultrasonic transducer at a predetermined sweep frequency B. C. Calculate the active power being used by the ultrasound transducer based on the monitoring signal. Control the AC driver to modulate the AC drive signal to maximize the active power used by the ultrasound transducer D. E. Storing in memory a record of the maximum active power used by the ultrasound transducer and the sweep frequency of the AC drive signal. Repeat steps AD a predetermined number of times, with each iteration increasing or decreasing the sweep frequency such that after a predetermined number of iterations, the sweep frequency increases or decreases from the sweep start frequency to the sweep end frequency.F. G. Determine from the records stored in memory the optimal frequency of the AC drive signal, which is the sweep frequency of the AC drive signal at which maximum active power is used by the ultrasound transducer. The AC driver is controlled to output an AC drive signal to the ultrasonic transducer at an optimal frequency to drive the ultrasonic transducer and atomize the liquid.

In some examples, the active power monitoring arrangement comprises a current sensing arrangement for sensing a drive current of an alternating current drive signal driving the ultrasound transducer, and the active power monitoring arrangement comprises a monitoring signal indicative of the sensed drive current. I will provide a.

In some examples, the current sensing arrangement includes an analog-to-digital converter that converts the sensed drive current into a digital signal for processing by the processor.

In some examples, the memory, when executed by the processor, instructs the processor to repeat steps A-D above in which the sweep frequency increases from a sweep start frequency of 2900 kHz to a sweep end frequency of 2960 kHz. I remember.

In some examples, the memory, when executed by the processor, instructs the processor to repeat steps A-D above in which the sweep frequency increases from a sweep start frequency of 2900 kHz to a sweep end frequency of 3100 kHz. I remember.

In some examples, the memory, when executed by the processor, causes the processor to: in step G, output an AC drive signal to the ultrasound transducer at a frequency shifted by a predetermined shift amount from the optimal frequency; Stores instructions to control.

In some examples, the predetermined shift amount is between 1 and 10% of the optimal frequency.

2. Control & Information (CI) Department
The control/information section consists of an external EEPROM for data storage, an LED for user display, a pressure sensor for detecting airflow, and a Bluetooth Low Energy (BLE) compatible microcontroller for constant monitoring and management of the aerosolization section. There is.

The pressure sensor used in this device serves two purposes. The first purpose is to prevent unnecessary and accidental starting of the sonic engine (activation of the ultrasonic transducer). This feature is implemented in the device's processing arrangement, which is optimized for low power consumption and incorporates environmental parameters such as temperature and ambient pressure to accurately detect and classify what is called a true inhalation. Constant measurement is performed using internal correction and reference settings.

Unlike all other mist inhalers on the market, this solution takes advantage of the microcontroller's strengths, making it possible to use only one sensor.

The second purpose of the pressure sensor is that it can not only accurately monitor the user's inhalation time for accurate inhalation volume measurement, but also is an important information in medical settings for proper prescribing and monitoring of health conditions. The aim is to enable people to judge the strength of their inhalation. Overall, we can fully inhale the pressure profile of every inhalation and be able to predict the end of inhalation for both aerosolization optimization and operational understanding of medical data.

This was made possible using a Bluetooth ^™ Low Energy (BLE) microcontroller. This allows for extremely precise inhalation times, optimized aerosolization, monitoring of numerous parameters to ensure safe misting, prevention of the use of non-genuine e-liquids and aerosol chambers, use of devices against the risk of overheating and over-misting. Unlike other products on the market, it is now possible to achieve both personal protection and personal protection at once.

The use of a BLE microcontroller enables over-the-air updates to continuously provide users with improved software based on anonymized data collection and trained AI for PZT modeling.

3. Power Management (PM) Department The power management department is responsible for the LDO (Low Dropout Regulator), which supplies power to the control/information section from a 3.7V LiPo battery, and the BMS (Battery Management System), which provides high protection and charging for the built-in LiPo battery. It consists of a path.

The components in this section were carefully and thoroughly selected in order to achieve a high power supply to the ultrasonic irradiation section and a stable power supply to the control/information section despite being an integrated and compact device. has been done.

In fact, when supplying high power to the aerosolization unit from a 3.7V lipo battery, the power supply voltage fluctuates significantly during operation. Without a low dropout regulator, it would not be possible to provide the necessary stable power to the control and information section when the battery voltage drops to 0.3V below the minimum rating of the components in this section. LDOs play an important role here. For this reason, LDOs play an important role. Loss of the CI section causes the entire device to stop functioning.

Therefore, careful selection of components not only ensures high reliability of the device, but also allows it to operate under harsh conditions and extend the time between charges.

Controlled Aerosolization This device must provide controlled and reliable aerosolization to be an accurate, reliable and safe aerosolization solution for medical prescriptions and daily customer use.
This is performed by internal methods that can be divided into several sections as follows.

1. Ultrasonication To achieve optimal aerosolization, the ultrasonic transducer (PZT) must be vibrated in the most efficient manner.

Frequency Due to the electromechanical properties of piezoelectric ceramics, the component is most efficient at its resonant frequency. However, if PZT continues to resonate for a long time, parts will inevitably break and the aerosol chamber will become unusable.

Furthermore, important points when using piezoelectric materials include variations during manufacturing and variations due to temperature and life.

To make the PZT resonate at 3 MHz to produce sub-1 um droplets, adaptations are required to locate and target a specific PZT "sweet spot" within all aerosol chambers used in the device for each inhalation. A method is needed.

Sweeps Because of the need to identify the "sweet spot" for each inhalation, and because of overuse, PZT's temperature is varied using an in-house double sweep method.

The first sweep is used when the device has not been used in a particular aerosol chamber for a time that is considered sufficient for all heat dissipation to occur and for the PZT to cool to the "default temperature." This procedure is also called a cold start. During this procedure, the PZT requires a boost to generate the necessary aerosol. This is achieved by taking into account extensive research and experimentation and passing only a small subset of frequencies between 2900kHz and 2960kHz that cover the resonance point.

Each frequency within this range causes the sonic engine to fire and the current passing through the PZT to be actively monitored and stored by the microcontroller via an analog-to-digital converter (ADC) to accurately determine the power used by the PZT. is converted into an electric current so that it can be subtracted.

This provides a cold profile of the PZT with respect to frequency, and the frequency used during inhalation is the one that uses the most current, ie the one with the lowest impedance.

A second sweep is performed during a subsequent inhalation, covering the entire frequency range between 2900 kHz and 3100 kHz by modifying the PZT profile with respect to temperature and deformation. This hot profile is used to determine the shifts to apply.

Shift Because aerosolization must be optimal, no shift is used during cold inhalation and the PZT will oscillate at a resonant frequency. This cannot happen unless repeated in a short period of time, otherwise the PZT will inevitably fail.

However, shifting is used during most inhalations as a way to target low impedance frequencies, achieving suboptimal operation of the PZT while protecting against failure.

Since the hot and cold profiles are stored during inhalation, the microcontroller can select the appropriate shift frequency according to the measurement of the current flowing through the PZT during the sweep, ensuring safe mechanical operation.

The selection of the direction of shift is important because the piezoelectric component behaves differently outside and inside the double resonance/antiresonance frequency. Since PZT is inductive and not capacitive, the shift selected should always be in this range defined by the resonant and anti-resonant frequencies.

Finally, the shift percentage is kept below 10% so that it is close to the lowest impedance but well away from resonance.

Adjustments Due to the essential nature of PZT, each inhalation will be different. In addition to the piezo element, numerous parameters influence the outcome of the inhalation, such as the amount of e-liquid remaining in the aerosol chamber, the wicking condition of the gauze, and the battery level of the device.

For this reason, the current used by the PZT in the aerosol chamber is constantly monitored, and the microcontroller constantly adjusts parameters such as frequency and duty cycle to provide the most stable power within a predefined range to the aerosol chamber. and is based on the most optimal and safe aerosolization research and experimental results.

Battery Monitoring In order to supply an AC voltage of 15V and maintain the current inside the PZT at about 2.5A, the current from the battery reaches about 7 to 8A, causing a drop in battery voltage. Typical lipo batteries cannot sustain this demanding resource for more than 6 seconds of inhalation.

Therefore, we developed a custom lipo battery that can handle approximately 11A, which is more than 50% of the maximum allowable current of PZT, and made it simple to use as a compact, integrated portable device.

Because the battery voltage drops and fluctuates significantly when the ultrasound generator is activated, the microcontroller constantly monitors the power used by the PZT in the aerosol chamber to ensure proper and safe aerosol generation.

Additionally, since control is the key to aerosolization, this device first ensures that the control and information section of the device is always functional and does not stop to the detriment of the ultrasonic processing section.

For this reason, the adjustment method takes into account the real-time battery level to a large extent and, if necessary, changes parameters such as duty cycle to maintain the battery at a safe level and, if necessary, changes parameters such as the duty cycle to maintain the battery at a safe level. If this occurs, the control and information section will prevent the engine from starting.

Power Control It is said that control is the key to aerosolization, and the method used in this device is a real-time, multidimensional function that constantly takes into account the profile of the PZT, the current inside the PZT, and the battery level of the device. .

All of this can only be achieved through the use of a microcontroller that can monitor and control every element of the device to achieve optimal inhalation.

1. Inhalation Control Although this device is a safe device as confirmed by the Broughton Nicotine Services (BNS) report, each inhalation must be controlled to ensure mist safety and the integrity of both the aerosol chamber and device. be.

Inhalation time To reduce exposure to harmful components such as carbonyls that can be generated by heating e-liquid, the maximum inhalation time is set to 6 seconds to completely limit exposure to these components.

Because it relies on interval piezoelectric components, the ultrasound irradiator will not operate when inhalation stops. The safety delay between two inhalations is adapted by the duration of the previous inhalation. This ensures that the gauze is properly suctioned before the next actuation.

This feature allows the device to operate safely and allows for more optimal aerosolization without damaging the PZT element or exposing the user to toxic components.

Connectivity (BLE)
The control/information section of the device is comprised of a wireless communication system using a Bluetooth Low Energy compatible microcontroller. The wireless communication system is configured to communicate with the device's processor and to send and receive data between the driver device and a computing device, such as a smartphone.

Bluetooth Low Energy connectivity with companion mobile applications is superior to traditional wireless connectivity solutions such as Wi-Fi, traditional Bluetooth, GSM, and even LTE-M and NB-IOT due to the low power required for this communication. It is possible to keep the device functioning for a long time even if it is not used at all.

Most importantly, this connectivity enables OTP as a function and complete control and safety of inhalation.

All data, from the resonant frequency of the inhalation used or created by the user to the negative pressure and duration, is stored and transferred via BLE for further analysis and improvement of the embedded software.

Moreover, all this information is extremely useful when the device is used in a medical program, as it provides doctors and users with all information about the inhalation process and allows real-time tracking of prescriptions and usage. is important.

Finally, this connectivity allows for embedded firmware updates within the device and over-the-air (OTA), ensuring that the latest version is always quickly deployed. This increases the scalability of the device and ensures that the device is maintained.

Data collection for clinical purposes User data such as number of puffs and duration of puffs can be collected to determine the total amount of treatment consumed by the user in one session.

This data can be interpreted by an algorithm that sets consumption limits by time of day based on physician recommendations.

This allows the user to receive a therapeutic dose of the drug that is controlled by a physician or pharmacist and cannot be abused by the end user.

A physician can gradually reduce the dosage over time in a controlled manner that is safe for the user.

Puff Limitations The process of ultrasonic cavitation has a significant impact on the nicotine concentration in the generated mist.

The device limitation of a puff time of 7 seconds or less limits the user's exposure to carbonyls commonly produced by electronic nicotine delivery systems.

According to experimental results from Broughton Nicotine Services, after a user performs 10 consecutive puffs of less than 7 seconds, the total amount of carbonyl formaldehyde is less than 2.67 μg/10 puffs (average: 1.43 μg/10 puffs). ), acetaldehyde less than 0.87 μg/10 puffs (average: 0.50 μg/10 puffs), propionaldehyde less than 0.40 μg/10 puffs (average: 0.40 μg/10 puffs), crotonaldehyde <0.16 μg /10 puffs (average: 0.16 μg/10 puffs), butyraldehyde <0.19 μg/10 puffs (average: 0.17 μg/10 puffs), diacetyl <0.42 μg/10 puffs (average: 0. (25 μg/10 puffs), no acetylpropionyl was detected in consecutive <7 second puff expulsions.

Aerosolization of e-cigarettes is achieved by the mechanical action of piezoelectric discs rather than by direct heating of the liquid, so the individual components of e-cigarettes (such as propylene glycol, vegetable glycerin, flavoring ingredients, etc.) remain largely intact. , it does not break down into smaller harmful components such as acrolein, acetaldehyde, and formaldehyde at the high rates found in traditional e-cigarettes.

To limit the user's exposure to carbonyls while using the ultrasound device, the puff length should be up to 6 seconds so that the above results are the absolute worst-case scenario in terms of exposure. limited to.

59 and 60, when the end cap 248 is attached to the driver device housing 246, the aluminum driver device housing 246 acts as a Faraday cage, preventing the device from emitting any electromagnetic radiation. The device with driver device housing 246 has been tested for electromagnetic compatibility (EMC), and testing has shown that emissions are less than half of the permissible limits for the device. The EMC test results are shown in the graph of FIG.

Other examples of the mist inhaler of the present disclosure consist of most or preferably all of the elements of the mist generating device 200 described above, but the memory of the driver device 202, when executed by the processor, provides the mist inhaler with additional functionality. and storing instructions for providing.

In one example, the mist inhaler 200 includes an active power monitor that incorporates a current sensor, such as current sensor 335 described above, to sense the rms drive current of the AC drive signal that drives the ultrasonic transducer 215. The active power monitor provides a monitoring signal indicative of sensed drive current, as described above.

An additional feature in this example allows the mist inhaler 200 to monitor the operation of the ultrasound transducer while the ultrasound transducer is operating. The mist inhaler 200 calculates an effectiveness value or quality index that indicates how effectively the ultrasound transducer is working to atomize liquid within the device. The device uses the effectiveness value to calculate the actual amount of mist generated over the duration of activation of the ultrasound transducer.

Once the actual amount of mist is calculated, the device calculates, based on the concentration of therapeutic agent in the liquid, the actual amount of therapeutic agent that was present in the mist, and therefore the actual amount of therapeutic agent inhaled by the user. configured to calculate a quantity. Knowing the exact amount of therapeutic agent delivered to the user is particularly important when the mist inhaler is used as part of a therapeutic treatment program. Knowing the exact amount of therapeutic agent delivered to the user during each inhalation or puff is simply the number of inhalations or puffs, assuming each inhalation or puff delivers the same amount of therapeutic agent to the user. Allows therapeutic treatment programs to be operated more accurately and effectively compared to using conventional devices that count.

In reality, as mentioned above, there are various factors that influence the operation of an ultrasound transducer and influence the amount of mist produced by the ultrasound transducer and thus the actual amount of therapeutic agent delivered to the user. exists.

If the ultrasonic transducer in the mist inhaler does not operate in an optimal manner, for example because a low charge of the battery reduces the current flowing through the ultrasonic transducer, there will be less A smaller amount of mist will be generated and a smaller amount of therapeutic agent will be delivered to the user. Therefore, the device is designed to deliver a set amount of therapeutic agent to the user over a period of time compared to the number of puffs that would be allowed if the ultrasound transducer was operating optimally. A higher number of puffs can be tolerated. This allows therapeutic treatment programs to operate more effectively and accurately compared to conventional programs that rely on the use of devices that simply count and limit the number of puffs taken by the user.

Next, configurations of some examples of mist inhalers and methods of generating mist using the mist inhalers will be described in detail below.

In this example, the mist inhaler incorporates the components of the mist inhaler 200 described above, but the memory of the driver device 202, when executed by the processor, causes the processor to direct the mist generating device 200 for a first predetermined period of time. It also remembers the command to activate it. As mentioned above, the mist generator is activated by driving the ultrasonic transducer 215 within the mist generator 200 with an alternating current drive signal such that the ultrasonic transducer 215 atomizes the liquid carried by the capillary element 222. .

The executed instructions cause the processor to sense the current of the AC drive signal flowing through the ultrasonic transducer 215 periodically during a first predetermined period of time using a current sensor, and to detect the periodically measured current value. Cause it to be stored in memory.

The executed instructions cause the processor to calculate the effect value using the current value stored in memory. The effectiveness value indicates the effectiveness of the ultrasonic transducer's operation in atomizing liquid.

In one example, the executed instruction causes the processor to calculate the validity value using this equation:

In one example, the memory, when executed by the processor, causes the processor to periodically measure a duty cycle of an alternating current drive signal driving the ultrasound transducer during a first predetermined period of time; Stores instructions that cause cycle values to be stored in memory. The mist inhaler then modifies the analog-to-digital converter side effect value Q _A based on the current value stored in memory. As a result, the mist inhaler of this example takes into account duty cycle variations that may occur through activation of the ultrasound transducer 215 when the device calculates the effectiveness value. Thus, the mist inhaler can accurately calculate the amount of mist actually produced by taking into account variations in the duty cycle of the AC drive signal that may occur while the ultrasonic transducer is operating.

In one example, the memory, when executed by the processor, causes the processor to periodically measure a voltage of a battery powering the mist generator for a first predetermined period of time; Stores instructions to store battery voltage values in memory. The mist inhaler then modifies the side effect value Q _A of the analog-to-digital converter based on the battery voltage value stored in the memory. As a result, the mist inhaler of this example takes into account variations in battery voltage that may occur during operation of the ultrasound transducer 215 when the device calculates the effectiveness value. The mist inhaler is therefore able to accurately calculate the amount of mist actually generated, taking into account battery voltage fluctuations that may occur while the ultrasonic transducer is operating.

The effectiveness value measures the actual amount of mist produced by the mist inhaler by proportionally reducing the value of the maximum amount of mist that would be produced by the mist inhaler if the device was operating optimally. Used as a weight to calculate quantities.

In one example, the memory, when executed by the processor, causes the processor to periodically measure the frequency of the alternating current drive signal driving the ultrasound transducer 215 during a first predetermined period of time; Stores instructions that store values in memory. The device then calculates the effect value using the frequency value stored in the memory in addition to the current value, as described above.

In one example, the memory, when executed by the processor, causes the processor to store a maximum amount of mist that would have been generated if the ultrasonic transducer 215 was operating optimally for a first predetermined length of time. Stores instructions to calculate values. In one example, the maximum amount of mist value is calculated based on modeling that determines the maximum amount of mist that would occur when the ultrasound transducer was operating optimally.

Once the maximum amount of mist value is calculated, the mist inhaler proportionally reduces the maximum amount of mist value based on the efficacy value over a first predetermined length of time duration. By determining the actual amount of mist generated, the actual amount of mist value can be calculated.

Once the actual mist volume is calculated, the mist inhaler can calculate a therapeutic volume value that represents the amount of therapeutic agent in the actual mist volume generated over a first predetermined length of time duration. The mist inhaler then stores a record of the therapeutic dose value in memory. In this way, the mist inhaler can accurately record the actual amount of therapeutic agent delivered to the user with each inhalation or puff.

In one example, the memory stores instructions that, when executed by the processor, cause the processor to select the second predetermined length of time in response to the validity value. In this case, the second predetermined length is the length of time that the ultrasound transducer 215 is activated during the second inhalation or puff by the user. In one example, the second predetermined length of time is equal to the first predetermined length of time, but proportionally decreased or increased according to the validity value. For example, if the effectiveness value indicates that the ultrasound transducer 215 is not operating effectively, the effectiveness value may cause the desired amount of mist to be generated during a second predetermined length of time. The second predetermined length of time is increased.

For the next inhalation, the mist inhaler operates the mist generator for a second predetermined time period such that the mist generator generates a predetermined amount of mist during the second predetermined time period. In this way, the mist inhaler accurately determines the amount of mist produced during the second predetermined time period, taking into account the various parameters reflected by the effectiveness value that influence the operation of the mist inhaler. Control.

In one example, the memory stores instructions that, when executed by the processor, cause the processor to operate the mist generator for a plurality of predetermined lengths of time. For example, the mist generating device is activated during multiple consecutive inhalations or puffs by the user.

The mist inhaler stores a plurality of therapeutic dose values in memory, each therapeutic dose value being indicative of a therapeutic dose in the mist produced over a respective one duration of a predetermined length of time. In one example, the mist inhaler prevents further activation of the mist generator for a predetermined duration if the total amount of therapeutic agent in the mist produced for a predetermined duration of time is greater than or equal to a predetermined threshold. do. In one example, the predetermined duration is a duration within the range of 1 hour to 24 hours. In other examples, the predetermined duration is 24 hours or 12 hours.

Mist inhalers of some examples of the present disclosure transmit data indicative of therapeutic dose values from a mist generator to a computing device (e.g., via Bluetooth ^™ Low Energy communication) and to a computing device (e.g., a smartphone). ) is configured to be stored in memory. An executable application running on the computing device can record the amount of therapeutic agent provided to the user. The executable application may also control the operation of the mist inhaler to limit the operation of the mist inhaler to limit the amount of therapeutic agent delivered to the user over a period of time.

Accordingly, the mist inhalers of some examples of the present disclosure provide additional information once a user has consumed a set amount of therapeutic agent during a set time frame, such as the amount of therapeutic agent consumed during a day. configured to prevent actuation.

All of the above applications involving ultrasound technology can benefit from the optimization achieved by a frequency controller that optimizes the frequency of sonication for optimal performance.

It will be appreciated that the disclosure herein is not limited to use for nicotine delivery. Indeed, in some instances, the mist inhaler includes a liquid containing a nicotine-free therapeutic agent. Some examples are configured for use for various medical purposes (eg, delivery of CBD for pain relief, supplements for performance enhancement, albuterol/salbutamol for asthma patients, etc.).

The devices disclosed herein are for use with any therapeutic agent, drug, or other compound, where the drug or compound is provided in a liquid within a liquid chamber of the device for aerosolization by the device. Ru. In some examples, the devices disclosed herein are for use with therapeutic agents, drugs, and compounds including, but not limited to:

Respiratory system
Brocodilator Olodaterol Levalbuterol Berodual (ipratropium bromide/fenoterol)
Combivent (ipratropium bromide/salbutamol)

Anti-inflammatory drugs Betamethasone Dexamethasone Methylprednisolone Hydrocortisone

Mucolytic agent N-acetylcysteine

Pulmonary hypertension Sildenafil Tadalafil Epoprostenol Treprostenil Iloprost

Infectious disease antibiotics Aminoglycosides (gentamicin, tobramycin, amikacin, colomycin, neomycin, liposomal amikacin,)
Quinolone antibacterial agents (ciprofloxacin, levofloxacin, moxifloxacin, ofloxacin)
Macrolides (azithromycin)
Minocycline beta-lactams (piperacillin/tazobactam, ceftazidime, ticarcillin, etc.)
Cephalosporins (Cefotaxime, Cefepime, Ceftriaxone, Cefotaxime)
Glycopeptide (vancomycin)
Meropenem polymyxin (colistin, polymyxin B)

Antifungal agents amphotericin fluconazole caspofungan

Antiviral agents Valganciclovir Favipiravir Remdesivir Acyclovir Antituberculosis Isoniazid Pyrazinamide Rifampin Ethambutol

Oncology biologics Zilotrif Afatinib Caplacizumab Dupilumab Isarilumab Allilcomab Volasertib Nintedanib Imatinib Sirolimus

Chemotherapy Azacytidine Decitabine Docetaxel Gemcitabine Cisplatinum

Central nervous system/psychiatric Sodium valproate Teriflunomide Zomitriptan

Metabolism/Hormone Insulin Estrogen

Immunology vaccines Monoclonal antibodies Stem cells

vitamin zinc ascorbic acid

Others Niclosamide Hydroxychloroquine Ivermectin

Some example ultrasonic mist inhalers 100 are more powerful versions of current portable medical nebulizers.

Other examples of ultrasonic mist inhalers are readily envisioned, including drug delivery devices that do not have the appearance of a cigarette.

The foregoing has outlined the features of some examples or embodiments to enable those skilled in the art to better understand various aspects of the disclosure. Those skilled in the art will readily utilize this disclosure as a basis for designing or modifying other processes and structures to accomplish the same purpose and/or achieve the same advantages of the various examples or embodiments introduced herein. You should understand that you can use Those skilled in the art will also appreciate that such equivalent constructions do not depart from the spirit and scope of this disclosure, and that they may make various changes, substitutions, and modifications to this document without departing from the spirit and scope of this disclosure. You should be aware that you can.

Although the subject matter has been described in language specific to structural features or methodological acts, it is understood that the subject matter of the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing at least a portion of the claims.

Various operations of examples or embodiments are provided herein. The order in which some or all of the operations are described should not be construed to imply that these operations are necessarily order dependent. It will be appreciated that alternative orders would have the benefit of this document. Furthermore, it will be appreciated that not all operations are necessarily present in each embodiment provided herein. It will also be appreciated that in some examples or embodiments, not all operations may be necessary.

Additionally, "exemplary" is used herein to mean serving as an example, instance, illustration, etc., and not necessarily as an advantage. As used herein, "or" is intended to mean an inclusive or rather than an exclusive or. Furthermore, as used in this application and the appended claims, "a" and "an" generally refer to "one or more," unless the context indicates otherwise or it is clear from context that the singular is intended. be interpreted as meaning. Further, to the extent that the words "comprising," "having," "having," "having," or variations thereof are used, such terms are intended to be inclusive in the same manner as the term "comprising." There is. Further, unless otherwise specified, "first", "second", etc. are not intended to imply temporal aspects, spatial aspects, order, etc. Rather, such terms are used only as identifiers, names, etc. of features, elements, items, etc. For example, the first element and the second element generally correspond to element A and element B, or two different elements or two identical elements or the same element.

Additionally, while this disclosure has been shown and described with respect to one or more embodiments, equivalent changes and modifications will occur to others skilled in the art based on a reading and understanding of this disclosure and the accompanying drawings. Probably. This disclosure includes all such changes and modifications, and is limited only by the scope of the following claims. In particular, with respect to various functions performed by features described above (e.g., elements, resources, etc.), the terminology used to describe such features, unless otherwise indicated, is consistent with the disclosed structure and structure. Although not equivalent, it is intended to correspond to any feature that performs a given function of the described feature (eg, is functionally equivalent). Additionally, although certain features of the present disclosure may have been disclosed with respect to only one of several embodiments, such features may be desirable or advantageous for any given or particular application. may be combined with one or more other features of other embodiments to

Examples or embodiments of the subject matter and functional operations described herein may be implemented in digital electronic circuits, or in computer software, firmware, or hardware, including the structures disclosed herein and structural equivalents thereof. , or a combination of one or more thereof.

Some examples or embodiments are implemented using one or more modules of computer program instructions encoded on a computer-readable medium for execution by or controlling the operation of a data processing device. be done. A computer-readable medium can be an article of manufacture, such as a hard drive in a computer or embedded system. The computer-readable medium can be obtained separately and later encoded with one or more modules of computer program instructions, such as by delivery of one or more modules of computer program instructions over a wired or wireless network. . A computer readable medium can be a machine readable storage device, a machine readable storage substrate, a storage device, or a combination of one or more thereof.

The terms "computing device" and "data processing apparatus" encompass all apparatus, devices, and machines for processing data, including, by way of example, a programmable processor, a computer, or multiple processors or computers. In addition to hardware, the device includes code that creates an execution environment for the computer program, such as processor firmware, a protocol stack, a database management system, an operating system, a runtime environment, or a combination of one or more thereof. It is possible to include. Additionally, the device may employ a variety of different computing model infrastructures, such as web services, distributed computing, grid computing infrastructure, etc.

The processes and logic flows described herein may be executed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and producing output. It is possible.

Processors suitable for the execution of a computer program include, by way of example, general and special purpose microprocessors, and any processor or processors of any kind of digital computer. Generally, a processor will receive instructions and data from read-only memory, random access memory, or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer is operable to receive data from and/or transfer data to one or more mass storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks. or both. However, a computer does not need to have such a device. Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices.

In this document, "compose" means "including" and "composing" means "including".

The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, may be found in the foregoing description, or in the following claims, or in the accompanying drawings, in their specific form or as means for performing the disclosed functions, or for achieving the disclosed results. The present invention is appropriately expressed in terms of a method or a process and can be utilized to realize the invention in its various forms, either separately or in any combination of its features.

Typical Features Typical features are listed in the following clauses, which may be used alone or in any combination with one or more features disclosed in the text and/or drawings of this document. can.

1. A mist inhaler for producing a mist containing a therapeutic agent for inhalation by a user, the device comprising:

A mist generator that includes:
A mist generator housing that is elongate and includes an air inlet port and a mist outlet port; A liquid chamber within the mist generator housing that contains a liquid to be atomized, the liquid containing a therapeutic agent; a sonication chamber disposed within the housing; a capillary element extending between the liquid chamber and the sonication chamber, wherein a first portion of the capillary element is within the liquid chamber and a second portion of the capillary element is within the liquid chamber; an ultrasonic transducer having an atomizing surface, wherein a portion of the second portion of the capillary element overlaps a portion of the atomizing surface; When driven by an alternating current drive signal, the atomizing surface vibrates to atomize the liquid carried by the second portion of the capillary element, generating a mist containing atomized liquid and air within the sonication chamber. Sonic Transducer Air flow between the air inlet port, the sonication chamber and the air outlet port such that the user aspirating at the mist exit port draws air from the inlet port, through the sonication chamber, and out the mist exit port. An airflow arrangement providing a path through which the mist generated in the sonication chamber is carried by air through a mist exit port and inhaled by a user, and includes:

Driver device containing:
an H-bridge circuit connected to the battery ultrasound transducer, the H-bridge circuit configured to generate an alternating current drive signal for driving the ultrasound transducer;

A microchip connected to an H-bridge circuit to control the H-bridge circuit and generate an alternating current drive signal, the microchip being a single unit consisting of a plurality of interconnected embedded components and subsystems. , a microchip containing:
an oscillator configured to generate:
Main Clock Signal A first phase clock signal that is high for a first time during a positive half period of the main clock signal and low during a negative half period of the main clock signal. a second phase clock signal that is high for a second period of time and low during a positive half period of the main clock signal, the first phase clock signal and the second phase clock signal a second phase clock signal, the phase of which is center-aligned;

A pulse width modulation (PWM) signal generator subsystem that includes:
the first phase clock signal and the second phase clock signal are configured to generate a double frequency clock signal, the double frequency clock signal being twice the frequency of the main clock signal; a delay locked loop configured to control a rising edge of the first phase clock signal and the second phase clock signal to be synchronized with a rising edge of the double frequency clock signal; A locking loop adjusts the frequency and duty cycle of the first phase clock signal and the second phase clock signal in response to the driver control signal to generate a first phase output signal and a second phase output signal. 2. The first phase output signal and the second phase output signal are configured to generate an AC drive signal that drives an H-bridge circuit to drive an ultrasound transducer. a first phase output signal terminal configured to output the first phase output signal to the H-bridge circuit; a second phase output signal terminal configured to output the second phase output signal to the H-bridge circuit; Phase Output Signal Terminal A feedback input terminal configured to receive a feedback signal from the H-bridge circuit when the H-bridge circuit is driving the ultrasonic transducer with an AC drive signal to atomize a liquid. , a feedback input terminal in which the feedback signal indicates a parameter of the operation of the H-bridge circuit or the AC drive signal.

An analog-to-digital converter (ADC) subsystem that includes:
a plurality of ADC input terminals configured to receive a plurality of respective analog signals, one ADC input terminal of the plurality of ADC input terminals configured to cause the ADC subsystem to receive a feedback signal from the H-bridge circuit; the ADC subsystem is configured to sample the analog signal received at the plurality of ADC input terminals at a sampling frequency proportional to the frequency of the main clock signal; a plurality of analog signal analogizers configured to generate ADC digital signals using the analog signals; receiving the ADC digital signals from the ADC subsystem; and processing the ADC digital signals to generate driver control signals. a digital processing device configured to control the PWM signal generation subsystem by communicating driver control signals to the PWM signal generation subsystem;

A digital-to-analog converter (DAC) subsystem that includes:
a digital-to-analog converter configured to convert a digital control signal generated by the digital processor subsystem to an analog voltage control signal to control a voltage regulator circuit that generates a voltage for modulation by the H-bridge circuit; instrument (DAC)
controlling the voltage regulation circuit to generate a predetermined voltage for modulation by the H-bridge circuit for driving the ultrasonic transducer in response to a feedback signal indicative of operation of the ultrasonic transducer; A DAC output terminal configured to output an analog voltage control signal.

2. A device according to clause 1, in which the microchip comprises:
A frequency divider connected to the oscillator and receiving a main clock signal from the oscillator, the frequency divider being configured to divide the main clock signal by a predetermined divisor and output a frequency reference signal to the delay locked loop. frequency divider

3. 2. The device according to claim 1 or 2, wherein the delay locked loop comprises a plurality of delay lines connected end to end, and the total delay time of the delay lines is equal to the period of the main clock signal. .

4. 4. The apparatus of claim 3, wherein the delay-locked loop is configured to control the first phase clock signal and the first phase clock signal in response to the driver control signal by varying the delay of each delay line in the delay-locked loop. one configured to adjust the duty cycle of a two-phase clock signal.

5. According to any one of the preceding clauses, the feedback input terminal is configured to receive a feedback signal from the H-bridge circuit in the form of a voltage indicative of the effective current of the alternating current drive signal driving the resonant circuit. Device.

6. Any one of the preceding clauses, wherein the ADC subsystem comprises a plurality of further ADC input terminals configured to receive a feedback signal indicative of at least one of the voltage of the battery or the voltage of a battery charger connected to the device. The device described in.

7. A device according to any one of the preceding clauses, wherein the microchip further comprises:
a temperature sensor embedded within the microchip, the temperature sensor configured to generate a temperature signal indicative of the temperature of the microchip, the temperature signal being coupled to a further ADC input terminal of the ADC subsystem; and the temperature signal is sampled by the ADC.

8. The apparatus of any one of the preceding clauses, wherein the ADC subsystem is configured to sample each signal received at the plurality of ADC input terminals a predetermined number of times with each signal sampled by the ADC subsystem.

9. A device according to any one of the preceding clauses, wherein the microchip further comprises:
a battery charging subsystem configured to control charging of the battery;

10. Apparatus according to any one of the preceding clauses, wherein the DAC subsystem further comprises:
A further digital-to-analog converter (DAC) configured to convert further digital control signals generated by the digital processor subsystem into further analog voltage control signals for controlling the voltage regulator circuit.

11. A device according to any one of the preceding clauses, the device further comprising:
A further microchip, wherein said further microchip is a single unit comprising a plurality of interconnected embedded components and subsystems:

First power supply terminal Second power supply terminal An H-bridge circuit incorporating a first switch, a second switch, a third switch, and a fourth switch, where:

The first switch and the third switch are connected in series between the first power terminal and the second power terminal. 2. The method of claim 1, wherein the first output terminal is electrically connected between the first power terminal and the second power source. a second switch and a fourth switch are connected in series between the second switch and the fourth switch; a second output terminal is electrically connected between the second switch and the fourth switch; The ultrasonic transducer of claim 1, wherein a second output terminal is connected to a second terminal of the ultrasonic transducer.

a first phase terminal configured to receive a first phase output signal from a pulse width modulated (PWM) signal generator subsystem; and a first phase terminal configured to receive a second phase output signal from the PWM signal generator subsystem. 2 phase terminal

generating a timing signal based on the first phase output signal and the second phase output signal, and outputting the timing signal to a switch of the H-bridge circuit, so that the H-bridge circuit drives the ultrasonic transducer. a digital state machine configured to control said switches on and off in a sequence to output an AC drive signal of said first switch and said second switch; 3 switches and a free float period in which the fourth switch is turned on, and the switch is turned to dissipate the energy stored by the ultrasonic transducer.

An electric wire that contains:
a first current sensing resistor connected in series between the first switch and the first power supply terminal; a voltage drop across the first current sensing resistor; and a current flowing through the first current sensing resistor. a first voltage sensor configured to provide a first voltage output indicative of a second current sensing resistor connected in series between the second switch and the first power supply terminal; a second voltage sensor configured to measure a voltage drop across a second current sensing resistor and provide a second voltage output indicative of current flowing through the second current sensing resistor; a current sensor output terminal configured to output an effective voltage to ground equal to the first voltage output and the second voltage output;

The effective output voltage is the effective current flowing through the first switch or the second switch and the current flowing through the ultrasonic transducer connected between the first output terminal and the second output terminal. The ultrasonic transducer according to claim 1, which shows:

12. Clause 11, wherein the H-bridge circuit is configured to output a power of 22W to 50W to the ultrasonic transducer connected between the first output terminal and the second output terminal. Device.

13. The device according to clause 11 or 12, further comprising:
a temperature sensor embedded within the further microchip, wherein the temperature sensor measures the temperature of the further microchip, and when the temperature sensor senses that the further microchip is at a temperature above a predetermined threshold; a temperature sensor configured to disable at least a portion of the temperature sensor;

14. The apparatus according to any one of clauses 11 to 13, further comprising:
A boost converter circuit configured to increase the voltage of a battery to a boost voltage in response to an analog voltage output signal from a DAC output terminal, the boost voltage being modulated by switching a switch in an H-bridge circuit. a boost converter circuit configured to provide a boost voltage at the first power supply terminal.

15. The current sensor is configured to sense a current flowing through the resonant circuit during the free float period, and the digital state machine determines whether the current flowing through the resonant circuit during the free float period is zero. 15. The device according to any one of clauses 11 to 14, configured to adapt a timing signal to switch on either the first switch or the second switch when sensed by a sensor. Device.

16. Apparatus according to any one of clauses 11 to 15, wherein during the setup phase of operation of the device the further microchip is configured as follows:
Measure the length of time it takes for the current flowing through the resonant circuit to reach zero when the first and second switches are turned off and the third and fourth switches are turned on. ,
The length of time of the free float period is set to be equal to the measured length of time.

17. A device according to any one of the preceding clauses, the device further comprising:
a processor for controlling the driver device; a memory storing instructions that, when executed by the processor, cause the driver device to:
A. Controlling the driver device to output an AC drive signal at a sweep frequency to the ultrasonic transducer B. C. Calculate the active power being used by the ultrasound transducer based on the feedback signal. D. Controlling the driver device to modulate the AC drive signal to maximize the active power used by the ultrasound transducer.D. E. Storing in memory a record of the maximum active power used by the ultrasound transducer and the sweep frequency of the AC drive signal. Repeat steps AD a predetermined number of times, with each iteration increasing or decreasing the sweep frequency such that after a predetermined number of iterations, the sweep frequency increases or decreases from the sweep start frequency to the sweep end frequency.F. G. Determine from the records stored in memory the optimum frequency of the AC drive signal, which is the sweep frequency of the AC drive signal at which maximum active power is used by the ultrasound transducer. The driver device is controlled to output an AC drive signal to the ultrasonic transducer at an optimal frequency to drive the ultrasonic transducer and atomize the liquid.

18. 18. The apparatus of clause 17, wherein the starting sweep frequency is 2900kHz and the ending sweep frequency is 3100kHz.

19. Apparatus according to any one of the preceding clauses, wherein the driver device is releasably attached to the mist-generating device such that the driver device is separable from the mist-generating device.

20. A mist inhaler for producing a mist for inhalation by a user, the device comprising:

Mist generator, comprising:
an ultrasonic treatment chamber; a liquid chamber containing a liquid to be atomized; a capillary element extending between the liquid chamber and the sonication chamber; an ultrasonic transducer that is conveyed from the liquid chamber to the sonication chamber by the capillary element; A device configured to vibrate to atomize liquid contained in the sonication chamber and generate a mist of atomized liquid and air within the sonication chamber. a mist outlet port in fluid communication with the sonication chamber for inhaling the mist inhaler, wherein the mist inhaler further includes:

Driver device containing:
Battery AC driver for converting the voltage from the battery into an AC drive signal to vibrate the ultrasound transducer To monitor the active power used by the ultrasound transducer when it is driven by an AC drive signal an active power monitor, the active power monitor including a current sensor for sensing a drive current of an alternating current drive signal driving the ultrasonic transducer, the active power monitor arrangement having a monitoring signal indicative of the sensed drive current; an active power monitor arrangement, providing a processor for controlling the AC driver and receiving supervisory signals from the active power monitor; and a memory for storing instructions that, when executed by the processor, cause the processor to:

activating the mist generator for a first predetermined period of time, activating the mist generator generating the mist with an alternating current drive signal such that the ultrasonic transducer atomizes liquid carried by the capillary element; including driving an ultrasound transducer within the device;
Using a current sensor, periodically sense the current of the AC drive signal flowing through the ultrasonic transducer during a first predetermined time period, and store the periodically measured current value in a memory. the current value is used to calculate an effectiveness value, the effectiveness value indicating the effectiveness of the operation of the ultrasonic transducer in atomizing the liquid; and in response to said effectiveness value, a second predetermined period of time; Selecting a Length According to claim 1, the mist generating device is operated during the second predetermined time so that the mist generating device generates a predetermined amount of mist during the second predetermined time. Method described.

21. The apparatus of clause 20, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
Periodically measuring the frequency of an AC drive signal that drives the ultrasonic transducer during a first predetermined length of time, and storing the periodically measured frequency value in a memory.The frequency stored in the memory. Calculate the effectiveness value using the value

22. The apparatus of clause 21, wherein the memory stores instructions that, when executed by the processor, cause the processor to calculate the validity value using the formula:

23. The apparatus of clause 22, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
Periodically measuring the duty cycle of the alternating current drive signal driving the ultrasound transducer for a first predetermined length of time and storing the periodically measured duty cycle value in memory.
Modifying the analog-to-digital converter side effect value Q _A based on the current value stored in the memory.

24. 24. The apparatus of claim 22 or 23, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
Periodically measuring the voltage of a battery supplying power to the mist generator during a first predetermined period of time, and storing the periodically measured battery voltage value in a memory.The battery voltage stored in the memory. Based on the value, modify the side effect value Q _A of the analog to digital converter.

25. The apparatus of any one of the preceding clauses, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
calculating a value for the maximum amount of mist that would be generated if the ultrasonic transducer was operating optimally during the first predetermined length of time; calculating the maximum amount of mist based on the effectiveness value; An actual mist amount value is calculated to determine the actual amount of mist generated during the first predetermined time period by proportionally decreasing the large amount value.

26. 26. The apparatus of clause 25, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
Calculate a treatment amount value indicating a treatment amount included in the actual amount of mist generated during the first predetermined time period. Store the treatment amount value in a memory.

27. 27. The apparatus of clause 26, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
activating the mist generator for a plurality of predetermined lengths of time; storing a plurality of therapeutic dose values in memory, each therapeutic dose value being generated for a respective predetermined length of time; indicating a therapeutic amount in the mist; and preventing further activation of the mist generating device for a predetermined duration if the total amount of therapeutic agent in the mist produced for a predetermined length of time duration is greater than or equal to a predetermined threshold;

28. 27. The apparatus of clause 27, wherein the predetermined duration is within the range of 1 hour to 24 hours.

29. 29. The apparatus of claim 27 or 28, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
transmitting data indicative of the therapeutic dose value from the mist generator to the computing device and storing it in memory of the computing device;

30. A method of producing a mist for inhalation by a user, comprising:
Activating the mist generator for a first predetermined period of time, activating the mist generator causes the ultrasonic transducer to vibrate to atomize the liquid, and generate a mist containing the atomized liquid and air. driving an ultrasonic transducer in the mist generator with an alternating current drive signal so as to generate the ultrasonic transducer; and periodically measuring a current of the alternating current drive signal flowing through the ultrasonic transducer during the first predetermined time period. , store the periodically measured current values in the memory. The current values stored in the memory are used to calculate the effect value, and the effect value indicates the effectiveness of the operation of the ultrasonic transducer in atomizing the liquid. selecting a second predetermined length of time in response to the effectiveness value; operating the mist generator such that the mist generator generates a predetermined amount of mist during the second predetermined time; operating for the second predetermined time period.

31. A method as described in Article 30, comprising:
Periodically measuring the frequency of an AC drive signal that drives the ultrasonic transducer during a first predetermined length of time, and storing the periodically measured frequency value in a memory.The frequency stored in the memory. Calculate the effectiveness value using the value

32. A method as described in clause 31, comprising calculating a validity value using this formula:

33. A method as described in Article 32, comprising:
Periodically measuring the duty cycle of the alternating current drive signal driving the ultrasound transducer for a first predetermined length of time and storing the periodically measured duty cycle value in memory.
Modifying the analog-to-digital converter (“ADC”) side effect value Q _A based on the current value stored in the memory.

34. A method according to paragraph 32 or paragraph 33, comprising:
Periodically measuring the voltage of a battery supplying power to the mist generating device during a first predetermined period of time, and storing the periodically measured battery voltage value in a memory.The battery voltage stored in the memory. Based on the value, the analog-to-digital converter (“ADC”) side effect value Q _A is modified.

35. The method according to any one of paragraphs 30 to 34, further comprising:
calculating a value for the maximum amount of mist that would be generated if the ultrasonic transducer was operating optimally during the first predetermined length of time; calculating the maximum amount of mist based on the effectiveness value; An actual mist amount value is calculated to determine the actual amount of mist generated during the first predetermined time period by proportionally decreasing the large amount value.

36. A method as described in Article 35, comprising:
Calculating a treatment amount value indicating a treatment amount included in the actual amount of mist generated during the first predetermined time period; and storing the treatment amount value in a memory.

37. A method as described in Article 36, comprising:
activating the mist generator for a plurality of predetermined lengths of time; storing a plurality of therapeutic dose values in memory, each therapeutic dose value being generated for a respective predetermined length of time; indicating a therapeutic amount in the mist; and preventing further activation of the mist generating device for a predetermined duration if the total amount of therapeutic agent in the mist produced for a predetermined length of time duration is greater than or equal to a predetermined threshold;

38. The method of paragraph 37, wherein the predetermined duration is within the range of 1 hour to 24 hours.

39. A method according to paragraph 37 or paragraph 38, comprising:
transmitting data indicative of the therapeutic dose value from the mist generating device to the computing device for storage in the memory of the computing device;

Claims (19)

A mist inhaler device for producing a mist containing a therapeutic agent for inhalation by a user, the device comprising:
A mist generator,
a mist generator housing that is elongated and includes an air inlet port and a mist outlet port;
a liquid chamber disposed within the mist generator housing, the liquid chamber containing a liquid to be atomized, the liquid containing a therapeutic agent;
an ultrasonic treatment chamber provided within the mist generator housing;
a capillary element extending between the liquid chamber and the sonication chamber, a first portion of the capillary element being within the liquid chamber and a second portion of the capillary element being within the sonication chamber; a capillary element,
an ultrasonic transducer having an atomizing surface, wherein a portion of the second portion of the capillary element overlaps a portion of the atomizing surface, and when the ultrasonic transducer is driven by an alternating current drive signal; ultrasound causing the atomizing surface to vibrate and atomize the liquid carried by the second portion of the capillary element to generate a mist comprising the atomized liquid and air within the sonication chamber; a transducer, and
the air inlet port, the sonication chamber, and the mist outlet port, such that a user drawing at the mist outlet port draws air from the inlet port, through the sonication chamber, and out the mist outlet port; an air flow arrangement providing an air flow path between the ultrasonic treatment chamber and the mist generated in the sonication chamber, the mist being carried by the air from the mist exit port and inhaled by the user; comprising a mist generator, the mist inhaler device further comprising:
A driver device,
Battery,
an H-bridge circuit connected to the ultrasonic transducer, the H-bridge circuit configured to generate an AC drive signal for driving the ultrasonic transducer;
A microchip connected to the H-bridge circuit and controlling the H-bridge circuit to generate the AC drive signal, the microchip comprising:
An oscillator,
main clock signal,
a first phase clock signal that is high only during a positive half period of the main clock signal and low during a negative half period of the main clock signal; and
a second phase clock signal that is high again during the negative half period of the main clock signal and low during the positive half period of the main clock signal; an oscillator configured to generate a second phase clock signal, wherein the phases of the second phase clock signal and the second phase clock signal are center aligned;
A pulse width modulation (PWM) signal generator subsystem comprising:
a delay locked loop configured to generate a double frequency clock signal using the first phase clock signal and the second phase clock signal, the double frequency clock signal being the main clock signal; and the delay locked loop is configured to control rising edges of the first phase clock signal and the second phase clock signal to be synchronized with rising edges of the double frequency clock signal. configured, the delay locked loop adjusts the frequency and duty cycle of the first phase clock signal and the second phase clock signal in response to a driver control signal to output the first phase output signal and the second phase clock signal. the first phase output signal and the second phase output signal are configured to generate two phase output signals, the first phase output signal and the second phase output signal generating an alternating current drive signal that drives the H-bridge circuit to drive the ultrasound transducer. a delay-locked loop configured to
a first phase output signal terminal configured to output the first phase output signal to the H-bridge circuit;
a second phase output signal terminal configured to output the second phase output signal to the H-bridge circuit;
a feedback input terminal configured to receive a feedback signal from the H-bridge circuit when the H-bridge circuit is driving the ultrasonic transducer with an AC drive signal to atomize the liquid; , a feedback input terminal, wherein the feedback signal indicates a parameter of operation of the H-bridge circuit or the AC drive signal;
a PWM signal generator subsystem comprising;
An analog-to-digital converter (ADC) subsystem, the subsystem comprising:
a plurality of ADC input terminals configured to receive a plurality of respective analog signals, one ADC input terminal of the plurality of ADC input terminals configured to receive a plurality of analog signals from the H-bridge circuit; connected to the feedback input terminal to receive a feedback signal, the ADC subsystem sampling analog signals received at the plurality of ADC input terminals at a sampling frequency proportional to the frequency of the main clock signal; an ADC subsystem comprising a plurality of ADC input terminals configured such that the ADC subsystem uses the sampled analog signal to generate an ADC digital signal;
a digital processor subsystem configured to receive the ADC digital signal from the ADC subsystem and process the ADC digital signal to generate the driver control signal; a digital processor subsystem configured to communicate control signals to the PWM signal generator subsystem to control the PWM signal generator subsystem; and
A digital-to-analog converter (DAC) subsystem comprising:
a digital-to-analog converter configured to convert a digital control signal generated by the digital processor subsystem to an analog voltage control signal to control a voltage regulator circuit that generates a voltage for modulation by the H-bridge circuit; instrument (DAC), and
controlling the voltage regulator circuit to generate a predetermined voltage for modulation by the H-bridge circuit for driving the ultrasonic transducer in response to a feedback signal indicative of operation of the ultrasonic transducer; a single unit comprising a plurality of interconnected embedded components and subsystems, including a digital-to-analog converter (DAC) subsystem comprising a DAC output terminal configured to output the analog voltage control signal; The device further comprises a driver device including a microchip. 2. The device according to claim 1, wherein the microchip comprises:
A frequency divider connected to the oscillator and receiving the main clock signal from the oscillator, the frequency divider dividing the main clock signal by a predetermined divisor and outputting a frequency reference signal to the delay locked loop. An apparatus further comprising a frequency divider configured. 3. The apparatus of claim 1 or claim 2, wherein the delay locked loop comprises a plurality of delay lines connected end-to-end, the total delay of the delay lines being equal to the period of the main clock signal. ,Device. 4. The apparatus of claim 3, wherein the delay-locked loop generates the first phase clock signal and the first phase clock signal in response to the driver control signal by varying the delay of each delay line in the delay-locked loop. Apparatus configured to adjust the duty cycle of the second phase clock signal. 5. Apparatus according to any one of claims 1 to 4, wherein the feedback input terminal receives a signal from the H-bridge circuit in the form of a voltage indicative of the effective current of an AC drive signal driving the resonant circuit. An apparatus configured to receive a feedback signal. 6. The device of any one of claims 1 to 5, wherein the ADC subsystem comprises a feedback signal indicative of at least one of the voltage of the battery or the voltage of a battery charger connected to the device. An apparatus comprising a plurality of further ADC input terminals configured to receive. 7. The device according to claim 1, wherein the microchip further comprises:
a temperature sensor embedded within the microchip, the temperature sensor configured to generate a temperature signal indicative of the temperature of the microchip, the temperature signal being coupled to a further ADC input terminal of the ADC subsystem; and the temperature signal is sampled by the ADC. 8. The apparatus of any one of claims 1 to 7, wherein the ADC subsystem is configured to each receive a signal received at the plurality of ADC input terminals together with each signal sampled by the ADC subsystem. An apparatus configured to sequentially sample a predetermined number of times. 9. The device according to claim 1, wherein the microchip further comprises:
An apparatus comprising a battery charging subsystem configured to control charging of the battery. 10. The apparatus according to claim 1, wherein the DAC subsystem comprises:
a further digital-to-analog converter (DAC) configured to convert further digital control signals generated by the digital processor subsystem into further analog voltage control signals for controlling the voltage regulator circuit; Device. The device according to any one of claims 1 to 10, wherein the device further comprises:
A further microchip, said further microchip comprising:
a first power terminal;
a second power terminal;
The H-bridge circuit includes a first switch, a second switch, a third switch, and a fourth switch,
the first switch and the third switch are connected in series between the first power terminal and the second power terminal,
a first output terminal is electrically connected between the first switch and the third switch, the first output terminal is connected to a first terminal of the ultrasonic transducer,
the second switch and the fourth switch are connected in series between the first power terminal and the second power terminal,
a second output terminal is electrically connected between the second switch and the fourth switch, and the second output terminal is connected to a second terminal of the ultrasonic transducer. , the H-bridge circuit,
a first phase terminal configured to receive the first phase output signal from the pulse width modulated (PWM) signal generator subsystem;
a second phase terminal configured to receive a second phase output signal from the PWM signal generator subsystem;
generating a timing signal based on the first phase output signal and the second phase output signal; and outputting the timing signal to the switch of the H-bridge circuit, so that the H-bridge circuit controls the ultrasound transducer. a digital state machine configured to control said switches on and off in sequence to output an alternating current drive signal for driving, said sequence dissipating energy stored by said ultrasound transducer; a digital state machine including a free float period in which the first switch and the second switch are turned off and the third switch and the fourth switch are turned on to
A current sensor,
a first current sensing resistor connected in series between the first switch and the first power supply terminal;
a first voltage sensor configured to measure a voltage drop across the first current sensing resistor and provide a first voltage output indicative of current flowing through the first current sensing resistor;
a second current sensing resistor connected in series between the second switch and the first power supply terminal;
a second voltage sensor configured to measure a voltage drop across the second current sensing resistor and provide a second voltage output indicative of current flowing through the second current sensing resistor; and
a current sensor output terminal configured to provide an effective output voltage to ground equal to the first voltage output and the second voltage output;
The effective output voltage is the effective current flowing through the first switch or the second switch, and the current flowing through the ultrasonic transducer connected between the first output terminal and the second output terminal. and a current sensor,
A device comprising a further microchip that is a single unit comprising a plurality of interconnected embedded components and subsystems, including: 12. The apparatus of claim 11, wherein the H-bridge circuit outputs a power of 22W to 50W to the ultrasonic transducer connected between the first output terminal and the second output terminal. A device configured as follows. 13. The device according to claim 11 or claim 12, wherein the further microchip comprises:
a temperature sensor embedded within said further microchip, said temperature sensor measuring the temperature of said further microchip, said temperature sensor sensing that said further microchip is at a temperature above a predetermined threshold; and a temperature sensor configured to disable at least a portion of the further microchip. The device according to any one of claims 11 to 13, wherein the device further comprises:
a boost converter circuit configured to increase the voltage of the battery to a boost voltage in response to the analog voltage control signal from the DAC output terminal, the boost voltage causing the switch of the H-bridge circuit to An apparatus comprising a boost converter circuit configured to provide the boost voltage at the first power supply terminal to be modulated by switching. 15. Apparatus according to any one of claims 11 to 14, wherein the current sensor is configured to sense a current flowing through a resonant circuit during the free float period, and the digital state machine comprises: adapting the timing signal to switch on either the first switch or the second switch when the current sensor senses that the current flowing through the resonant circuit is zero during the free float period; A device configured to: 16. A device according to any one of claims 11 to 15, wherein during a set-up phase of operation of the device, the further microchip:
the length of time it takes for the current flowing through the resonant circuit to reach zero when the first switch and the second switch are turned off and the third switch and the fourth switch are turned on; measure the
Apparatus configured to set the length of time of the free float period to be equal to the measured length of time. 17. The device according to any one of claims 1 to 16, wherein the device further comprises:
a processor for controlling the driver device; and
a memory for storing instructions that, when executed by the processor, cause the driver device to:
A. controlling the driver device so that the ultrasonic transducer outputs an AC drive signal at a sweep frequency;
B. calculating the active power being used by the ultrasound transducer based on the feedback signal;
C. controlling the driver device to modulate the AC drive signal to maximize the active power being used by the ultrasound transducer;
D. storing in the memory a record of the maximum active power used by the ultrasonic transducer and the sweep frequency of the AC drive signal;
E. After a predetermined number of iterations have occurred, repeating steps AD for the predetermined iterations, with each iteration increasing or decreasing the sweep frequency such that the sweep frequency increases or decreases from a starting sweep frequency to an ending sweep frequency. Repeat several times,
F. determining from the record stored in the memory the optimum frequency of the AC drive signal that is the sweep frequency of the AC drive signal at which maximum active power is used by the ultrasound transducer;
G. controlling the driver device to output an AC drive signal to the ultrasonic transducer at the optimum frequency to drive the ultrasonic transducer to atomize the liquid;
A device that has memory that stores instructions. 18. The apparatus of claim 17, wherein the starting sweep frequency is 2900 kHz and the ending sweep frequency is 3100 kHz. 19. A device according to any one of claims 1 to 18, wherein the driver device is releasably attached to the mist generator such that the driver device is separable from the mist generator. equipment.